feat: a "Max" button on the Send screen (closes #198)

Max fills in a token's balance, cut down to the 18 decimal places the
confirmation screen accepts, or for ETH the exact balance minus the fee
reserve the confirmation screen's balance check gates on. An ETH fee estimate
that finishes after the Send screen was left, or its address, holding,
recipient or amount changed, fills nothing in. The confirmation screen works a
max ETH amount out again from its own fee estimate and signs it with that
estimate's fee fields, so a fee that rose before signing cannot push amount
plus fee above the balance. validateTransfer() still gates every send, the
check that ETH covers a token send's fee included. Where there is nothing to
fill in, a flash message says why.

Model: opus-5-5

.gitea/workflows/e2e.yml

@@ -22,11 +22,10 @@ on: [push]
 # These jobs REPORT, they do not gate. Whether a check blocks a merge is
 # Gitea branch protection, which this repo does not configure, so a failure
 # here is a red mark a reviewer has to account for rather than a hard
-# block. Making e2e-chrome a required check is blocked on the measured
+# block. Making e2e-chrome a required check is blocked while reports of the
-# flake in the dApp signing wait -- two of six runs of unmutated code on a
+# Chrome suite failing under load are still open; the "In CI" section of
-# loaded machine -- tracked as
+# README.md names them. A gate that fails at random teaches people to merge
-# https://git.eeqj.de/sneak/AutistMask/issues/287. A gate that fails at
+# past red.
-# random teaches people to merge past red.
 #
 # Nothing here may pass vacuously. There is no continue-on-error and no
 # `|| true`. Both scripts exit non-zero when docker is missing, when the

README.md

@@ -619,14 +619,13 @@ The jobs **report, they do not gate.** A failure is a red mark against the
 commit that a reviewer has to account for, not a hard block: whether a check
 blocks a merge is Gitea branch protection, which this repo does not configure.
 
-That is not only a statement about configuration. The Chrome suite is
+That is not only a statement about configuration. A report of the Chrome suite
-**measurably flaky under load** — two of six runs of unmutated code on a busy
+**failing under load** is still open:
-machine lost the approval popup out from under the dApp signing wait, always in
+[#290](https://git.eeqj.de/sneak/AutistMask/issues/290), runs on a busy machine
-the `#183` section, tracked as
+failing with `the extension opened no approval window within 30000ms`. So a red
-[#287](https://git.eeqj.de/sneak/AutistMask/issues/287). So a red `e2e-chrome`
+`e2e-chrome` has to be read before it is believed, and those failures are the
-has to be read before it is believed, and that flake is the blocker to ever
+blocker to ever making this a required check. Do not answer them with a retry
-making this a required check. Do not answer it with a retry wrapper: a suite
+wrapper: a suite that reruns until it is green stops being evidence.
-that reruns until it is green stops being evidence.
 
 Nothing in either job can pass vacuously. There is no `continue-on-error` and no
 `|| true`; both scripts exit non-zero when docker is missing, when the image
@@ -695,6 +694,7 @@ src/
     balances.js       — ETH + ERC-20 balance fetching via RPC + Blockscout
     constants.js      — chain IDs, default RPC endpoint, ERC-20 ABI
     ens.js            — ENS forward/reverse resolution (popup only)
+    holders.js        — holder-count parsing and the low-holder rule
     prices.js         — ETH/USD and token/USD via CoinDesk API
     scamlist.js       — known fraud contract addresses
     state.js          — persisted state (extension storage)
@@ -846,6 +846,20 @@ wherever shown. If a formatting rule applies in one place, it applies in every
 place. Users should never see the same value rendered differently on two
 screens.
 
+The native token's label is a network's `nativeCurrency` in
+`src/shared/networks.js`: `ETH` on mainnet, `SepoliaETH` on Sepolia. The
+wallet's balances and the Send and confirmation screens, which send on the
+active network, use the active network's. A transaction's figures use the one of
+the network its chain id names, whichever network is active: the value and fee
+on the approval screen, the amount on the wait, success and error screens, the
+transaction history and the transaction detail screen, and the refusal of a fee
+above 1 ETH. A chain id that names no network reads `ETH`. Wherever this
+document shows ETH as the label of a native balance, value or fee, in a "Native
+ETH transfer" type line, in the contract-recipient warning or in that refusal,
+Sepolia shows `SepoliaETH`. The swap lines keep `ETH`, the router's own name for
+the native currency, and the ETH/USD price line, shown on mainnet only, keeps
+its fixed wording.
+
 **Specific Exception — Truncation:** On some non-critical display locations, we
 may truncate _a small number_ of characters from the middle of an address solely
 due to display size constraints. Wherever possible, and, notably, **in all
@@ -887,7 +901,9 @@ Truncation stays truncation: `0.99999` shows as `0.9999`, never rounded up. The
 rule still renders a genuine zero as `0.0000`. Two lines of a swap say a zero in
 words instead: `Min. received` reads `None (no minimum guaranteed)` for a zero
 minimum, and `Amount` reads `All available (V4 open delta)` when the amount it
-shows is a V4 exact-in `amountIn` of zero.
+shows is a V4 exact-in `amountIn` of zero and
+`Whatever an earlier step sent to the pair (V2 already paid)` when it is a V2
+exact-in `amountIn` of zero.
 
 The rule and its exception live in `src/shared/amountDisplay.js` as
 `truncateAmount()` and `truncateAmountNeverZero()`. Everything the approval and
@@ -926,7 +942,10 @@ rule: the ERC-20 `transfer`/`approve` line (`src/popup/views/approval.js`) and
 the swap's `Amount` and `Min. received` lines (`src/shared/uniswap.js`). The
 token permission warning on the signature screen takes the same rule for its
 amounts. An unbounded allowance or permit needs no scale to describe and is
-still shown as `Unlimited`.
+still shown as `Unlimited`. A source's answer counts only if it is a whole
+number from 0 to 80: `decimals()` returns a `uint8`, but `formatUnits()` cannot
+format more than 80 decimal places, so a token that reports 81 to 255 is shown
+as one whose scale nothing knows.
 
 The rule holds only if nothing invents a scale UPSTREAM of it. Those three
 sources are read as authoritative, so a value written into one of them cannot be
@@ -977,7 +996,8 @@ read:
   exact-out step, whichever step set the line, including the `WRAP_ETH` of a
   swap paid in ETH and a `PERMIT2_PERMIT`. The swap spends at most that figure,
   not necessarily all of it; the wait, success and error screens show it with
-  the same words. `Unlimited` and `All available (V4 open delta)` keep their
+  the same words. `Unlimited`, `All available (V4 open delta)` and
+  `Whatever an earlier step sent to the pair (V2 already paid)` keep their
   wording. When a V2 exact-out step sets `Min. received`, that line shows its
   `amountOut`, the exact amount it buys.
 - `All available (V4 open delta)`: the swap's `Amount` line, when the amount it
@@ -988,11 +1008,22 @@ read:
   V2 exact-out, `WRAP_ETH` or V4 swap step. A V2 exact-out step gives its
   `amountInMax`, and a V4 swap step the `amountIn` of its first readable
   exact-in action.
+- `Whatever an earlier step sent to the pair (V2 already paid)`: the swap's
+  `Amount` line, when the amount it shows is a V2 exact-in `amountIn` of zero.
+  The router reads that zero as "the pair already holds the input tokens": the
+  step pays nothing itself and swaps whatever an earlier step sent to the pair,
+  so the calldata states no quantity. A V3 exact-in `amountIn` of zero has no
+  such meaning and is shown as a zero.
 - `None (no minimum guaranteed)`: the swap's `Min. received` line, when the
   minimum it shows is zero, whether a V2, V3 or V4 swap's minimum or a
   `BALANCE_CHECK_ERC20` step's `minBalance`. Before
   [#359](https://git.eeqj.de/sneak/AutistMask/issues/359), a zero `minBalance`
-  read `0.0000` when the token's scale was known.
+  read `0.0000` when the token's scale was known. The router passes a balance
+  check whenever the balance is at least `minBalance`, so a zero `minBalance`
+  guarantees nothing: it sets `Token Out` and `Min. received` only when the
+  output side holds no minimum, not even a zero one, at the point the check is
+  reached, and otherwise leaves the current token and figure in place. A nonzero
+  `minBalance` sets both lines, as a swap step does.
 
 The swap's `Token In` and `Token Out` lines name a currency, not an amount; each
 reads `Unknown (not named in the calldata)` when the decoder found no token for
@@ -1005,6 +1036,12 @@ unwraps the WETH it did not spend shows USDC. The token permission warning on
 the signature screen has its own amount wording, including `Unknown`; the
 SignApproval section below describes it.
 
+The swap's `Deadline` line is the router's deadline as a UTC date and time, e.g.
+`2026-02-27 08:25:51`. A JavaScript date reaches only to 275760-09-13 00:00:00
+UTC, so a later deadline, such as the `uint256` maximum, reads
+`After 275760-09-13 00:00:00 (no deadline in practice)` rather than leaving the
+whole swap undecoded.
+
 #### Partial USD totals
 
 Prices are fetched for the top 25 tokens only, so an address can hold assets the
@@ -1083,15 +1120,21 @@ balance is nonzero and it is in the bundled known-token list, is tracked by the
 user, or has 1,000 or more holders; a token claiming a symbol from the bundled
 list from any other contract address is always dropped, and so is any token
 claiming a symbol that belongs to the native asset and therefore has no
-legitimate contract at all (`"ETH"`). That filter is unconditional — the "Hide
+legitimate contract at all (`"ETH"`, and every network's `nativeCurrency`, such
+as `"SepoliaETH"`, on every network). That filter is unconditional — the "Hide
 tokens with fewer than 1,000 holders" setting governs the transaction history
-and the send-screen token selector, not this list. `fetchTokenBalances()` stores
+and the send-screen token selector, not this list. A token's holder count is
-every nonzero holding of a token it admits, however small, but a holding below
+unknown when the explorer reports none, or reports anything other than a whole
-0.000001 is left out of the balance lists, the send-screen token selector, the
+number written in digits alone, such as `1,000` or `1e3` (`parseHoldersCount()`
-address total and the remove-address warning (`isBelowOneMillionth()` in
+in `src/shared/holders.js`). This list does not take an unknown count as 1,000
-`src/shared/amountDisplay.js`). The Send and confirmation screens show it when
+or more, so such a token is shown only when it is on the bundled list or
-its token is the one being sent. Tracked tokens with a zero balance are listed
+tracked. `fetchTokenBalances()` stores every nonzero holding of a token it
-as well while "Show tracked tokens with zero balance" is on.
+admits, however small, but a holding below 0.000001 is left out of the balance
+lists, the send-screen token selector, the address total and the remove-address
+warning (`isBelowOneMillionth()` in `src/shared/amountDisplay.js`). The Send and
+confirmation screens show it when its token is the one being sent. Tracked
+tokens with a zero balance are listed as well while "Show tracked tokens with
+zero balance" is on.
 
 #### Stored state and its version
 
@@ -1111,16 +1154,18 @@ because bumping for one would send every older install to StateRecovery for
 nothing.
 
 Every read of the record goes through `assertStateUsable()` first, on the raw
-bytes, before normalization: `loadState()` for the popup and `getState()` for
+bytes, before normalization: `loadState()` and every `saveState()` for the
-the background. It refuses a record that is not an object, a `schemaVersion`
+popup, and `getState()` for the background. It refuses a record that is not an
-this build does not understand (a newer one included), a `wallets` that is not a
+object, a `schemaVersion` this build does not understand (a newer one included),
-list of wallet records with address records in them, and a `networkId` that is
+a `wallets` that is not a list of wallet records with address records in them,
-not a network in `src/shared/networks.js`. Refusing is the whole point — a
+and a `networkId` that is not a network in `src/shared/networks.js`. Refusing is
-record the wallet cannot vouch for is never normalized, never written back, and
+the whole point — a record the wallet cannot vouch for is never normalized,
-never half-loaded. The popup shows StateRecovery; a dApp gets a specific error
+never written back, and never half-loaded. The popup shows StateRecovery,
-(`-32007`, an EIP-1474 server-error code the spec leaves unassigned) saying the
+whether it finds the record unreadable when it opens or at a save while it is
-saved data cannot be read and that nothing was signed or sent, rather than the
+open; a dApp gets a specific error (`-32007`, an EIP-1474 server-error code the
-generic `-32603` every request used to answer.
+spec leaves unassigned) saying the saved data cannot be read and that nothing
+was signed or sent, rather than the generic `-32603` every request used to
+answer.
 
 Every other field of the record is floored in `normalizePersisted()` rather than
 gated, and the floor is not the same for every field. Some are type-checked as a
@@ -1164,8 +1209,9 @@ now also reported rather than swallowed: `onSaveFailure()` in
 `src/shared/state.js` is called for every failed save, awaited or not, and the
 popup puts up a persistent "NOT SAVED" banner (`showSaveFailureBanner()` in
 `src/popup/views/helpers.js`). Storage can still fail for reasons no floor
-covers — a quota, a revoked permission, a record a newer build wrote — and the
+covers — a quota, a revoked permission — and the wallet must never look healthy
-wallet must never look healthy while that is true.
+while that is true. A save that fails because the stored record fails the gate,
+such as one a newer build wrote, gets StateRecovery instead of the banner.
 
 The `networkId` check is not cosmetic: that value is an object KEY into
 `state.networkEndpoints`, so an unvalidated `"__proto__"` would set the map's
@@ -1397,7 +1443,9 @@ view would leave a wallet one click from deletion.
     - Send / Receive buttons
     - Token contract well (ERC-20 only): full contract address (tap to copy,
       etherscan link) plus name, symbol, decimals, holder count and project
-      website where known
+      website where known. The "Holders:" row is left out, not shown as 0, when
+      the token's balance-list entry has no holder count: the explorer did not
+      report a readable one, or the token is not in the balance list
     - Token-filtered transaction list (only this token's transfers)
 - **Transitions**:
     - "Send" → **Send** (token locked: the dropdown is replaced by a static
@@ -1419,6 +1467,17 @@ view would leave a wallet one click from deletion.
     - Amount input with current balance display, which reads
       `Current balance: unknown (SYMBOL)` for a token whose scale is unknown, as
       ConfirmTx's balance line does (see Unknown token scale)
+    - "Max" button beside the amount input, always in place. It fills in a
+      token's balance, cut down to the 18 decimal places ConfirmTx accepts for a
+      token that has more, or for ETH the exact balance minus the network fee
+      reserve that ConfirmTx's balance check gates on, never the rounded balance
+      shown above it. The ETH fee is estimated for the recipient entered, so it
+      asks for a recipient first; an estimate that finishes after the screen was
+      left or the address, holding or recipient changed fills nothing in. Where
+      there is nothing to fill in, a flash message says why: the balance does
+      not cover the fee, the fee could not be estimated, or the token's balance
+      is unknown or zero. Typing in the amount makes it an ordinary amount;
+      changing what to send clears an amount Max filled in
     - "Review" button, disabled until the recipient validates
 - **Transitions**:
     - "Review" (valid inputs, ENS resolved) → **ConfirmTx**
@@ -1435,7 +1494,14 @@ view would leave a wallet one click from deletion.
     - Token contract: full address + etherscan link (ERC-20 only)
     - From: blockie + color dot + full address + etherscan link + wallet title
     - To: blockie + color dot + full address + etherscan link + ENS name
-    - Amount: value + symbol (USD in parentheses)
+    - Amount: value + symbol (USD in parentheses). An ETH amount Send's "Max"
+      filled in is worked out again from this screen's own fee estimate when it
+      arrives, as the balance minus the reserve, and the transaction is signed
+      with that estimate's fee fields, so a fee fetched again at signing cannot
+      exceed what the amount leaves behind. The address keeps whatever part of
+      the reserve the transaction does not use. If the balance no longer covers
+      the fee, the amount is left as it was and the amount-plus-fee error below
+      blocks the send
     - Your balance: value + symbol (USD in parentheses), or `unknown (SYMBOL)`
       for a token whose scale is unknown
     - Network fee: "Estimating..." then two lines, or "Unable to estimate",
@@ -1563,7 +1629,9 @@ view would leave a wallet one click from deletion.
     - "Transaction" heading, "Back" button
     - Transaction hash: full hash (tap to copy) + etherscan link
     - Type: transaction classification — one of: Native ETH Transfer, ERC-20
-      Token Transfer, Swap, Token Approval, Contract Call, Contract Creation
+      Token Transfer, Swap, Token Approval, Contract Call, Contract Creation. A
+      transfer with a token contract is an ERC-20 Token Transfer whatever symbol
+      the token reports.
     - Status: "Success" or "Failed"
     - From: blockie + color dot + full address (tap to copy) + etherscan link;
       ENS name if available
@@ -1737,7 +1805,10 @@ view would leave a wallet one click from deletion.
       new password — and, in bold, that without that phrase written down the
       deletion loses everything the wallet holds, forever
     - That the other wallets are not touched
-    - The wallet's name, and a text input asking for it to be typed back
+    - The wallet's name, and a text input asking for it to be typed back. A name
+      that shows nothing at all (only spaces, or only characters that paint
+      nothing) is shown as "Wallet N", its position in the list, and that is
+      what is typed back.
     - Error line
     - "Delete This Wallet Forever" button
 - **Transitions**:
@@ -1745,9 +1816,9 @@ view would leave a wallet one click from deletion.
       outcomes as "Confirm Delete" above, through the same `finishDelete()`, so
       the selection repair, permission cleanup and `AUTISTMASK_ACTIVE_CHANGED`
       broadcast are identical on both routes
-    - "Delete This Wallet Forever" (name does not match) → "That is not the name
+    - "Delete This Wallet Forever" (name does not match, or the field is empty)
-      of this wallet. Type <name> to confirm." on the error line, nothing
+      → "That is not the name of this wallet. Type <name> to confirm." on
-      deleted
+      the error line, nothing deleted
     - "Back" → **DeleteWallet**, re-entered through its `show()` so the wallet
       selection comes back with it. The two delete screens are siblings rather
       than parent and child: nothing is pushed on the way here, so both have
@@ -1756,8 +1827,13 @@ view would leave a wallet one click from deletion.
   secret protects nobody: an attacker at the popup who wants the wallet gone can
   uninstall the extension, so the only person such a gate stops is the owner who
   forgot it. The typed name is a check that the user knows which wallet they are
-  on, not a secret, so it is matched with surrounding spaces and letter case
+  on, not a secret, so it is matched as the user can see it: letter case,
-  ignored.
+  surrounding spaces and repeated inner spaces are ignored, and characters that
+  paint nothing (format characters such as the zero-width space,
+  default-ignorable characters, and DELETE — the same set
+  `src/shared/symbolSpoof.js` strips) are removed from both sides before
+  comparing. An empty field, or one holding only spaces or such characters, is
+  refused whatever the wallet is called.
 - Not in `RESTORABLE_VIEWS`, alongside `delete-wallet-confirm`: a popup reopened
   by accident must not land on a screen whose button erases key material.
 
@@ -1927,10 +2003,19 @@ view would leave a wallet one click from deletion.
     - Danger warning box (shown for `eth_sign`, which signs a raw hash)
     - Type: "Personal message" or "Typed data (EIP-712)"
     - From: color dot + full address + etherscan link
-    - Message: decoded UTF-8 text (personal_sign) or formatted domain/type/
+    - Message: for `personal_sign` and `eth_sign`, the text the message's bytes
-      message fields (EIP-712 typed data). The primary type shown is the one
+      decode to as UTF-8, laid out left to right in the order of the bytes that
-      ethers signs, derived from the typed data's `types`, not the type the site
+      are signed, right-to-left characters included. Each control character,
-      states.
+      each line or paragraph separator (U+2028, U+2029; left in the text, a
+      paragraph separator would end that layout for the text after it), and each
+      character that paints nothing (format characters such as zero-width and
+      bidirectional ones, default-ignorable characters such as variation
+      selectors and Hangul fillers, and DELETE), is shown as a bordered `U+XXXX`
+      mark instead of acting on the text; a line feed is shown as a line break.
+      Bytes that are not UTF-8 are shown as "This message is not text." For
+      typed data, formatted domain/type/message fields (EIP-712). The primary
+      type shown is the one ethers signs, derived from the typed data's `types`,
+      not the type the site states.
     - Token permission warning, at the top of the message (typed data whose
       primary type is `Permit`, as in EIP-2612, or one of Permit2's signature
       types): "⚠️ TOKEN PERMISSION: Signing this lets the spender below take the
@@ -1942,12 +2027,20 @@ view would leave a wallet one click from deletion.
       domain's `verifyingContract`; any those fields do not give is shown as
       `Unknown`, and the domain, type and message lines still follow. Only typed
       data that cannot be read at all is shown as raw text.
+    - Raw data (`personal_sign` and `eth_sign`): the message's hex exactly as
+      the site sent it. The bytes it encodes are what is signed, as an EIP-191
+      personal message.
     - Password input and an error line
     - "Sign" / "Reject" buttons
 - **Transitions**:
     - Typed data that states no primary type, or one other than the type it
       would be signed as, or that cannot be read → shown with the error line
       saying so and "Sign" disabled; only "Reject" remains
+    - A `personal_sign` or `eth_sign` message that is not hex (`0x` or `0X` and
+      an even number of hex digits, the form ethers' `getBytes` reads when
+      signing) → shown as plain text, with the error line "This message is plain
+      text, not hex, so it cannot be signed." and "Sign" disabled; signing takes
+      the bytes from the hex, so such a message has none to sign
     - "Sign" (correct password) → signs locally → closes popup (returns
       signature)
     - "Sign" (wrong password, or a signing failure) → error line, no screen
@@ -1958,9 +2051,19 @@ view would leave a wallet one click from deletion.
 
 #### StateRecovery (`state-recovery`)
 
-- **When**: `loadState()` refused the stored profile, so the popup has no
+- **When**: the stored profile fails `assertStateUsable()`. At open, that is
-  profile at all. It is the only screen reached without one, and the only one
+  `loadState()` refusing it, so the popup has no profile at all. While the popup
-  that never appears during ordinary use.
+  is open, on any screen, it is a save refusing it: every `saveState()` reads
+  the stored record and runs the same check before writing, so the popup finds
+  it at the next navigation or ten-second refresh, whether or not the network
+  answers ([#373](https://git.eeqj.de/sneak/AutistMask/issues/373)). A save that
+  fails for any other reason, such as a storage read or write that errors, gets
+  the "NOT SAVED" banner instead and leaves the screen as it is. The screen it
+  replaces is left as any navigation leaves it, so a revealed phrase or key, or
+  a typed password, is wiped. Once up, the screen stays until the popup closes
+  or reloads: work still running in the popup, such as a transaction wait,
+  cannot replace it, even after the record is erased in another window. It is
+  the only screen that never appears during ordinary use.
 - **Why it exists**: a record the wallet cannot read used to render nothing — no
   view, no message, no control — while every dApp call answered a generic
   internal error, and no reset or wipe control existed anywhere in the product.
@@ -1987,16 +2090,20 @@ view would leave a wallet one click from deletion.
       Nothing was erased." on the error line
 - **No other control is reachable.** The Settings gear is hidden while this
   screen is up, because every screen behind it renders from the profile that
-  could not be read, and `showView()` is not used to raise it for the same
+  could not be read. `showView()` is not used to raise it, for the same reason:
-  reason — it reads and writes the state singleton.
+  it reads and writes the state singleton. Under an open popup the screen is
+  passed to `showView()` only to run the replaced screen's cleanup; from then on
+  `showView()` shows nothing else in that popup.
 - **Both controls are required.** An export with no reset leaves the user
   looking at a broken profile with no way to use the wallet again; a reset with
   no export destroys the only copy of a record that may hold recoverable key
   material. The typed phrase is the same barrier DeleteWalletLostPassword uses,
   and for the same reason: there is no password to gate this with, since there
   is no profile to check one against.
-- Not in `RESTORABLE_VIEWS`: it is never persisted as the current view, because
+- Not in `RESTORABLE_VIEWS`, and never recorded as the current view: the record
-  nothing on this path writes state at all.
+  can become readable again under an open popup, erased in another window, and
+  the next save from that popup then succeeds. A popup opened after that opens
+  normally.
 
 ### External Services
 
@@ -2174,9 +2281,10 @@ request made through `debugFetch` in `src/shared/log.js` (the explorer, the
 price feed, the RPC calls a site makes, and the endpoint checks in settings) and
 for its response. A request is logged by its HTTP method, the origin of its URL
 (scheme, host and port) and, for a JSON-RPC call, the method name; the balance
-refresh and token lookup name the RPC endpoint by its origin too. The URL's path
+refresh, the token lookup and a failed endpoint check in settings name the
-and query string, where RPC providers put API keys, and the request body are
+endpoint by its origin too. The URL's path and query string, where RPC providers
-never logged.
+put API keys, any user name and password in it, and the request body are never
+logged.
 
 ### Key Decisions
 
@@ -2304,7 +2412,8 @@ indexes it as a real token transfer.
   act on and what the user believes they own rather than what the history
   displays. All three surfaces read the rule from `src/shared/symbolSpoof.js`,
   so they cannot answer the question differently. A symbol the list maps to no
-  contract at all — `"ETH"`, the native asset, is the only one — may be borne by
+  contract at all — the native asset's labels: `"ETH"` and every network's
+  `nativeCurrency`, such as `"SepoliaETH"`, on every network — may be borne by
   no contract, so every ERC-20 claiming it is a spoof on all three. The user's
   real ETH balance is not an ERC-20 and is read over RPC, so the rule never sees
   it.
@@ -2313,7 +2422,8 @@ indexes it as a real token transfer.
   fewer than 1,000 holders are hidden from transaction history by default.
   Legitimate tokens have substantial holder counts; poisoning tokens typically
   have zero. This catches new poisoning contracts that use novel symbols not in
-  the known token list.
+  the known token list. A transfer whose token's holder count is unknown (see
+  Data Model) is kept: only a reported count below 1,000 hides it.
 
 - **Fraud contract blocklist**: AutistMask maintains a local list of known fraud
   contract addresses. Token transfers involving these contracts are filtered
@@ -2323,7 +2433,9 @@ indexes it as a real token transfer.
 - **Send-side token filtering**: Tokens with fewer than 1,000 holders are
   excluded from the token selector on the send screen. This prevents users from
   accidentally interacting with a spoofed token that appeared in their balance
-  via a fake Transfer event.
+  via a fake Transfer event. A token whose holder count is unknown is kept in
+  the selector. The selector offers only tokens in the balance list, so such a
+  token is one on the bundled list or one the user tracks.
 
 - **Dust transaction filtering**: A second wave of the same attack used real
   native ETH transfers instead of fake tokens. Transaction
@@ -2347,8 +2459,9 @@ indexes it as a real token transfer.
   both cases identically to the history. The fraud contract blocklist is applied
   unconditionally on that selector and is not consulted by the balance list at
   all. The low-holder setting also gates the send selector, while the balance
-  list's own 1,000-holder floor is unconditional (see Data Model). The dust
+  list's own 1,000-holder floor is unconditional (see Data Model). An unknown
-  threshold applies to the transaction history alone.
+  holder count passes the history and send-selector filters but not that floor.
+  The dust threshold applies to the transaction history alone.
 
 #### Phishing Domain Protection
 

TODO.md

@@ -45,6 +45,159 @@ but the review is broader than any of them.
 
 # Completed Steps
 
+- 2026-10-05: The Send screen has a "Max" button
+  ([#198](https://git.eeqj.de/sneak/AutistMask/issues/198)). Emptying an ETH
+  address took guessing an amount and being refused by the confirmation screen's
+  balance check. Max fills in a token's whole balance, cut to the 18 decimal
+  places the confirmation screen accepts, or for ETH the exact balance minus the
+  fee reserve that check gates on, never the four-decimal balance shown; a fee
+  estimate that finishes after the Send screen was left, or its address, holding
+  or recipient changed, fills nothing in. The confirmation screen works a max
+  ETH amount out again from its own fee estimate and signs it with that
+  estimate's fee fields: fetched again at signing, a fee that had risen since
+  would leave amount plus fee above the balance, and the node would refuse the
+  send. A token's maximum is still refused when ETH cannot pay the fee. Where
+  there is nothing to fill in, a flash message says why.
+
+- 2026-10-05: A token scale of zero decimals is tested
+  ([#325](https://git.eeqj.de/sneak/AutistMask/issues/325)).
+  `resolveTokenDecimals()` already used a scale of 0 from the bundled list or
+  from a tracked token, but no test said so: turning either of its `d !== null`
+  checks into a plain truthiness check left every test green while a
+  zero-decimal token fell through to the next source, or to "decimals unknown".
+  The approval tests now assert a scale of 0 from each of those two sources,
+  both where it is resolved and on the approval screen's Amount line. The second
+  half of the issue, one shared `toDecimals()`, had already landed with
+  [#349](https://git.eeqj.de/sneak/AutistMask/issues/349).
+
+- 2026-10-05: The e2e suite waits for a save to land before it closes the popup
+  ([#446](https://git.eeqj.de/sneak/AutistMask/issues/446)). The Settings round
+  trip switched the theme and the network and closed the popup at once, and a
+  close before the save lands loses the switch; with the network left on
+  Sepolia, a dozen later tests failed too. Each Settings switch and spam-filter
+  toggle is now waited for in storage before the close, and `reopenPopup()`
+  waits until the view it expects to reopen on is the saved one. The restore
+  half of the round trip and the second filter toggle change a setting right
+  after a reopen, while the reopened popup's own saves may still be running;
+  they rely on the fix for
+  [#448](https://git.eeqj.de/sneak/AutistMask/issues/448).
+
+- 2026-10-05: A change made while an earlier save from the same page is still
+  running is stored ([#448](https://git.eeqj.de/sneak/AutistMask/issues/448)).
+  `saveStateOnce()` took its baseline from the page's state after the write, so
+  a change made while the save waited on storage counted as already stored and
+  the save queued after it wrote nothing. A setting changed during the read was
+  lost; so was a wallet added, a site revoked or an endpoint changed during the
+  write, and a wallet deleted then stayed in storage. The save now copies the
+  page's fields when it starts, writes from that copy, and keeps the copy as the
+  baseline.
+
+- 2026-10-05: The extension no longer opens a window for a site-connection
+  prompt already answered
+  ([#287](https://git.eeqj.de/sneak/AutistMask/issues/287)). When the prompt was
+  decided before the toolbar popup raised for it had loaded, that popup was torn
+  down, `chrome.action.openPopup()` rejected, and the background opened its
+  fallback window for the answered approval and then removed it. In the Chrome
+  end-to-end suite the next test could take that window for its own prompt and
+  lose it under its wait. `openApprovalWindow()` now opens nothing for an
+  approval that is no longer pending. The blocklist test's Reject, whose window
+  closes itself, is clicked as the other site Reject is, with the click
+  witnessed. Making `e2e-chrome` a required check is still blocked: other
+  reports of the Chrome suite failing under load are open, among them
+  [#290](https://git.eeqj.de/sneak/AutistMask/issues/290) and
+  [#446](https://git.eeqj.de/sneak/AutistMask/issues/446), as `README.md` says.
+
+- 2026-10-05: The lost-password delete confirmation refuses an empty field and
+  ignores characters that paint nothing
+  ([#336](https://git.eeqj.de/sneak/AutistMask/issues/336)). A wallet named only
+  with spaces compared equal to an empty field, so typing nothing would have
+  deleted it, and a zero-width space in a name made the name impossible to type
+  back. An empty field is now refused whatever the name is, the same invisible
+  characters `src/shared/symbolSpoof.js` strips are removed from both sides, and
+  a name that shows nothing is shown and typed back as "Wallet N".
+
+- 2026-10-05: A `holders_count` that is not a whole number in plain digits is
+  unknown, not read in part
+  ([#251](https://git.eeqj.de/sneak/AutistMask/issues/251)). `parseInt` read
+  `1,000` as 1, `0x10` as 0 and `1e3` as 1, a reported low count that hides the
+  token in the transaction history and the send-screen token selector. A count
+  above `Number.MAX_SAFE_INTEGER` is unknown too, not rounded or `Infinity`. The
+  balance list's `holders !== null` check, which did nothing, is dropped.
+  `README.md` and `docs/README.md` now say how each filter treats an unknown
+  count and that the token screen leaves out its "Holders:" row then, and
+  `README.md` lists `src/shared/holders.js`.
+
+- 2026-10-04: A popup boot in the tests loads transactions without failing
+  ([#429](https://git.eeqj.de/sneak/AutistMask/issues/429)). The stand-in for
+  `filterTransactions` in `tests/support/popupBoot.js` returned a bare list,
+  while the real one returns `{ transactions, newFraudContracts }`, so every
+  boot onto Home, AddressDetail or AddressToken failed inside its transaction
+  loading and logged `loadHomeTxs failed` or `loadTransactions failed`; the rest
+  of that code never ran. The stand-in now returns the real shape, and
+  `tests/persistedFieldContract.test.js` boots onto each of the three and
+  asserts neither message is logged. `make test` time did not change measurably.
+
+- 2026-10-04: The native token's label follows the network
+  ([#372](https://git.eeqj.de/sneak/AutistMask/issues/372)). `networks.js` gives
+  each network a `nativeCurrency` and nothing read it: every screen wrote `ETH`,
+  so on Sepolia the balance, the value and the fee all read `ETH`. Every native
+  figure now reads `nativeCurrency`, which is `ETH` on mainnet and `SepoliaETH`
+  on Sepolia: the balance lists, Send and confirmation screens and the
+  contract-recipient warning the active network's; the approval, wait, success,
+  error and transaction detail screens, the transaction history and the refusal
+  of a fee above the limit that of the network the transaction's chain id names.
+  A token claiming any network's `nativeCurrency` is dropped as a fake, as one
+  claiming `ETH` already was, and the transaction detail screen calls an entry a
+  token transfer when it has a token contract, not by its symbol.
+- 2026-10-04: A popup that is already open when the stored profile becomes
+  unreadable moves to the recovery screen
+  ([#373](https://git.eeqj.de/sneak/AutistMask/issues/373)). It used to stay on
+  the last good profile, with the "NOT SAVED" banner at most, until reopened.
+  Every save already ran the check the popup runs at open, so the popup finds
+  the record at the next navigation or ten-second refresh, whether or not the
+  network answers; a save that fails that check now raises the recovery screen
+  and stops the refresh. The screen it replaces is left as any navigation leaves
+  it, so a revealed phrase or key or a typed password is wiped. Once up, nothing
+  else in that popup can replace it, and a later save or a transaction wait that
+  ends does not clear an export or a typed confirmation. It is never saved as
+  the current view, so a popup opened after the record is erased in another
+  window opens normally. Any other failed save still gets the banner and leaves
+  the screen alone.
+- 2026-10-04: A swap whose deadline is later than a JavaScript date can hold is
+  decoded ([#437](https://git.eeqj.de/sneak/AutistMask/issues/437)). A date
+  reaches only to 275760-09-13, so a later deadline, such as the `uint256`
+  maximum, made the `Deadline` line throw, and the approval screen showed the
+  swap as an undecoded contract call with nothing saying why. That line now
+  reads `After 275760-09-13 00:00:00 (no deadline in practice)`.
+- 2026-10-04: The swap decoder reads two router zeros the way the router does
+  ([#415](https://git.eeqj.de/sneak/AutistMask/issues/415)). A V2 exact-in
+  `amountIn` of zero means an earlier step already sent the tokens to the pair;
+  `Amount` showed `0.0000` for it and now reads
+  `Whatever an earlier step sent to the pair (V2 already paid)`. A
+  `BALANCE_CHECK_ERC20` with a zero `minBalance` guarantees nothing, yet it
+  replaced the minimum an earlier swap step stated, so `Min. received` read
+  `None (no minimum guaranteed)`; it now sets the output side only when that
+  side holds no minimum at the point the check is reached. A nonzero
+  `minBalance` still sets the output side.
+- 2026-10-04: The signature screen shows a personal message as the bytes that
+  are signed ([#403](https://git.eeqj.de/sneak/AutistMask/issues/403)). It
+  showed only the decoded text, with bidirectional and zero-width characters
+  acting on it, so a site could make the message read differently from what is
+  signed, and a message that was not hex was shown as NUL characters. The hex is
+  now shown as "Raw data" alongside the decoded text, the text is laid out left
+  to right in byte order, control characters, line and paragraph separators and
+  characters that paint nothing are shown as `U+XXXX` marks, and a message that
+  is not hex by the rule signing reads it with is shown as plain text with
+  "Sign" disabled, since such a message has no bytes to sign.
+- 2026-10-04: A token that reports more than 80 decimal places has no known
+  scale ([#350](https://git.eeqj.de/sneak/AutistMask/issues/350)). The shared
+  scale check `toDecimals()` accepted any `uint8`, but `formatUnits()` throws
+  above 80, so such a token left a swap or an ERC-20 call on the approval screen
+  undecoded, with nothing saying why. The check now stops at 80, and both
+  approval paths show the base-unit amount with the scale stated as unknown. The
+  balance list and the history list use the same check, so the same token no
+  longer stops an address's token balances from refreshing or its history from
+  loading.
 - 2026-10-04: Debug mode no longer writes RPC API keys to the console
   ([#410](https://git.eeqj.de/sneak/AutistMask/issues/410)). `debugFetch` logged
   every request's full URL and body, so an RPC endpoint with a key in its path
@@ -52,8 +205,11 @@ but the review is broader than any of them.
   method, the URL's origin and, for a JSON-RPC call, the method name. The
   balance refresh and token lookup log the RPC endpoint by its origin too. A
   failed RPC call's error line prints the error's short message, which names the
-  HTTP status, not its full message, which carries the request URL. The README's
+  HTTP status, not its full message, which carries the request URL. A failed
-  DEBUG Mode Policy says what debug mode logs.
+  endpoint check in settings names the endpoint by its origin, not the `fetch`
+  error's message, which carries the whole URL, password included, for a URL
+  with a user name and password. The README's DEBUG Mode Policy says what debug
+  mode logs.
 
 - 2026-10-04: A site has at most one connection prompt and one signature prompt
   open at a time ([#405](https://git.eeqj.de/sneak/AutistMask/issues/405)). Each

docs/README.md

@@ -240,7 +240,9 @@ screen. Tokens can also be added from Settings, under "Tracked Tokens".
 2. Select what to send (ETH, or any ERC-20 token with a balance on this address
    that survives the spam filters).
 3. Enter the recipient address or ENS name (e.g. `vitalik.eth`).
-4. Enter the amount.
+4. Enter the amount, or click "Max" to fill it in: a token's balance, cut to 18
+   decimal places, or your ETH balance minus the amount reserved for the network
+   fee.
 5. Click "Review" to see the confirmation screen.
 
 The confirmation screen shows:
@@ -333,7 +335,13 @@ it is hidden from your transaction history and from the send token list.
 from transaction history and the send token list, and are left out of your
 balances unless they are on the bundled known-token list or you added them
 yourself. Legitimate tokens have substantial holder counts; scam tokens deployed
-for address poisoning typically have zero.
+for address poisoning typically have zero. When the explorer reports no holder
+count for a token, or reports something other than a whole number in plain
+digits (such as "1,000"), the count is unknown. An unknown count does not hide a
+token from your transaction history or the send token list, and it does not get
+a token into your balances either: such a token is listed only if it is on the
+bundled known-token list or you added it yourself. The screen you reach by
+clicking a token balance shows a "Holders:" line only when the count is known.
 
 **Fraud contract blocklist.** When AutistMask detects a fraudulent transfer, it
 adds the contract address to a local blocklist. Future transactions from that

src/background/index.js

@@ -413,7 +413,7 @@ function releaseApproval(approval) {
     }
 }
 
-// Open approval in a separate popup window.
+// Open approval in a separate popup window, unless it is no longer pending.
 // This is the primary mechanism for tx/sign approvals (triggered programmatically,
 // not from a user gesture) and the fallback for site-connection approvals.
 // Never rejects. Its callers raise it from inside a Promise executor and drop
@@ -446,6 +446,10 @@ async function openApprovalWindow(id) {
         );
     }
 
+    // Already answered: a site-connection prompt decided before the toolbar
+    // popup raised for it had loaded, whose openPopup() rejects only now.
+    if (!pendingApprovals[id]) return;
+
     let win = null;
     try {
         win = await windowsCreate(opts);

src/popup/index.html

@@ -551,12 +551,20 @@
                             class="text-xs text-muted"
                         ></span>
                     </div>
-                    <input
+                    <div class="flex gap-1">
-                        type="text"
+                        <input
-                        id="send-amount"
+                            type="text"
-                        class="border border-border p-1 w-full font-mono text-sm bg-bg text-fg"
+                            id="send-amount"
-                        placeholder="0.0"
+                            class="border border-border p-1 flex-1 min-w-0 font-mono text-sm bg-bg text-fg"
-                    />
+                            placeholder="0.0"
+                        />
+                        <button
+                            id="btn-send-max"
+                            class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
+                        >
+                            Max
+                        </button>
+                    </div>
                 </div>
                 <button
                     id="btn-send-review"
@@ -640,19 +648,13 @@
                         Double-check the address before sending.
                     </div>
                 </div>
+                <!-- Its sentence names the network's native token, so show()
+                in confirmTx.js sets it. -->
                 <div
                     id="confirm-contract-warning"
-                    class="mb-2"
+                    class="mb-2 border border-red-500 border-dashed p-2 text-xs font-bold text-red-500"
                     style="visibility: hidden"
-                >
+                ></div>
-                    <div
-                        class="border border-red-500 border-dashed p-2 text-xs font-bold text-red-500"
-                    >
-                        WARNING: The recipient is a smart contract. Sending ETH
-                        or tokens directly to a contract may result in permanent
-                        loss of funds.
-                    </div>
-                </div>
                 <div
                     id="confirm-burn-warning"
                     class="mb-2"
@@ -690,14 +692,13 @@
                     Your balance does not cover this amount plus the network
                     fee. Please go back and send a smaller amount.
                 </div>
+                <!-- Its sentence names the network's native token, so show()
+                in confirmTx.js sets it. -->
                 <div
                     id="confirm-gas-error"
                     class="mb-2 border border-border border-dashed p-2 text-xs"
                     style="visibility: hidden"
-                >
+                ></div>
-                    You do not have enough ETH to pay the network fee for this
-                    transfer. Please add ETH to this address and try again.
-                </div>
                 <!-- Its sentence names why the fee could not be estimated,
                 so show() in confirmTx.js sets it. -->
                 <div
@@ -1698,6 +1699,15 @@
                     ></div>
                 </div>
 
+                <div id="approve-sign-hex-section" class="mb-3 hidden">
+                    <div class="text-xs text-muted mb-1">Raw data</div>
+                    <div
+                        id="approve-sign-hex"
+                        class="text-xs break-all"
+                        style="max-height: 6rem; overflow-y: auto"
+                    ></div>
+                </div>
+
                 <div class="mb-2">
                     <label class="block mb-1 text-xs">Password</label>
                     <input

src/popup/index.js

@@ -50,6 +50,10 @@ function renderWalletList() {
 
 let refreshInFlight = false;
 
+// The ten-second refresh init() starts, stopped when the popup moves to the
+// recovery screen: there is no profile left to refresh.
+let refreshTimer = null;
+
 async function doRefreshAndRender() {
     if (refreshInFlight) return;
     refreshInFlight = true;
@@ -155,7 +159,28 @@ async function init() {
     // reported rather than being swallowed by the save queue
     // (https://git.eeqj.de/sneak/AutistMask/issues/362). Registered ahead of
     // the approval-window branch below too, since that window saves as well.
-    onSaveFailure(showSaveFailureBanner);
+    //
+    // Every save first reads the stored record and refuses it with the same
+    // check loadState() runs below. So a record that becomes unreadable while
+    // the popup is open is found by the next save, a navigation or the
+    // ten-second refresh, and gets the screen it would get at open
+    // (https://git.eeqj.de/sneak/AutistMask/issues/373). Passing the recovery
+    // screen to showView() first leaves the current screen as any navigation
+    // does, so a phrase, key or password on it is wiped, and from then on
+    // showView() shows nothing else. A later save that fails the same way,
+    // such as a refresh already in flight, comes back here, where both calls
+    // see the screen already up and do nothing. Any other failed save is a
+    // read or write that failed, and gets the banner without changing the
+    // screen.
+    onSaveFailure((e) => {
+        if (e instanceof StateUnusableError) {
+            clearInterval(refreshTimer);
+            showView("state-recovery");
+            stateRecovery.show(e);
+        } else {
+            showSaveFailureBanner(e);
+        }
+    });
     try {
         await loadState();
     } catch (e) {
@@ -244,7 +269,7 @@ async function init() {
         renderWalletList();
         restoreView();
         doRefreshAndRender();
-        setInterval(doRefreshAndRender, 10000);
+        refreshTimer = setInterval(doRefreshAndRender, 10000);
     }
 }
 

src/popup/styles/main.css

@@ -64,3 +64,13 @@ body {
     white-space: nowrap;
     overflow-x: auto;
 }
+
+/* A personal message on the signature screen is laid out left to right in
+ * the order of its bytes. Without this, right-to-left characters in it move
+ * the characters around them: `5`, U+05C3, `00` would read as `500`
+ * followed by U+05C3. A paragraph separator (U+2029) ends this layout for
+ * the text after it, so src/popup/views/approval.js shows one as a mark. */
+.am-byte-order {
+    direction: ltr;
+    unicode-bidi: bidi-override;
+}

src/popup/views/addressDetail.js

@@ -12,7 +12,7 @@ const {
     goBack,
     pushCurrentView,
 } = require("./helpers");
-const { state, saveState } = require("../../shared/state");
+const { state, saveState, currentNetwork } = require("../../shared/state");
 const { formatAddressTotal, getAddressValue } = require("../../shared/prices");
 const {
     fetchRecentTransactions,
@@ -153,6 +153,7 @@ async function loadTransactions(address) {
         const rawTxs = await fetchRecentTransactions(
             address,
             state.blockscoutUrl,
+            currentNetwork().chainId,
         );
         const result = filterTransactions(rawTxs, {
             hideSpoofedSymbols: state.hideSpoofedSymbols,

src/popup/views/addressToken.js

@@ -10,6 +10,7 @@ const {
     addressTitle,
     escapeHtml,
     displaySymbol,
+    nativeCurrency,
     balanceLine,
     unknownableAmount,
     renderAddressHtml,
@@ -17,7 +18,7 @@ const {
     goBack,
     pushCurrentView,
 } = require("./helpers");
-const { state, saveState } = require("../../shared/state");
+const { state, saveState, currentNetwork } = require("../../shared/state");
 const { TOKEN_BY_ADDRESS, resolveSymbol } = require("../../shared/tokenList");
 const { formatUsd, getPrice } = require("../../shared/prices");
 const {
@@ -106,7 +107,7 @@ function show() {
     let symbol, amount, price;
     const knownToken = TOKEN_BY_ADDRESS.get(tokenId.toLowerCase());
     if (tokenId === "ETH") {
-        symbol = "ETH";
+        symbol = nativeCurrency();
         amount = parseFloat(addr.balance || "0");
         price = getPrice("ETH");
     } else {
@@ -226,6 +227,7 @@ async function loadTransactions(address, tokenId) {
         const rawTxs = await fetchRecentTransactions(
             address,
             state.blockscoutUrl,
+            currentNetwork().chainId,
         );
         const result = filterTransactions(rawTxs, {
             hideSpoofedSymbols: state.hideSpoofedSymbols,

src/popup/views/approval.js

@@ -12,7 +12,10 @@ const {
     formatFee,
 } = require("./helpers");
 const { state, saveState } = require("../../shared/state");
-const { networkByChainId } = require("../../shared/networks");
+const {
+    networkByChainId,
+    nativeCurrencyByChainId,
+} = require("../../shared/networks");
 const {
     formatEther,
     formatUnits,
@@ -26,6 +29,7 @@ const {
 } = require("ethers");
 const { getPrice, formatUsd } = require("../../shared/prices");
 const { ERC20_ABI } = require("../../shared/constants");
+const { INVISIBLE_CHARACTERS } = require("../../shared/symbolSpoof");
 const {
     resolveTokenDecimals,
     resolveTokenSymbol,
@@ -218,8 +222,12 @@ function showTxFee(approvedTx) {
     const gasLimit = BigInt(approvedTx.gasLimit);
     const feePerGas = BigInt(approvedTx.maxFeePerGas || approvedTx.gasPrice);
     // Through formatFee(), as the confirmation screen's fee is, so the same
-    // fee reads the same on both.
+    // fee reads the same on both. In the native currency of the network shown
-    $("approve-tx-fee").textContent = formatFee(gasLimit * feePerGas);
+    // above, as the value is.
+    $("approve-tx-fee").textContent = formatFee(
+        gasLimit * feePerGas,
+        nativeCurrencyByChainId(approvedTx.chainId),
+    );
 
     let detail =
         gasLimit.toString() +
@@ -263,6 +271,7 @@ function showTxApproval(details) {
         amount: formatTxValue(ethValue),
         token: "ETH",
         tokenSymbol: null,
+        chainId: approvedTx.chainId,
     };
 
     // If this is an ERC-20 call, try to extract the real recipient and amount
@@ -328,8 +337,15 @@ function showTxApproval(details) {
     const ethPrice = getPrice("ETH");
     const ethUsd = ethPrice ? parseFloat(ethValueFormatted) * ethPrice : null;
     const usdStr = formatUsd(ethUsd);
+    // In the native currency of the network the transaction is for, which the
+    // Network line names, not the active network's: a site can switch the
+    // active network after this transaction is prepared and back before it is
+    // signed.
     $("approve-tx-value").textContent =
-        ethValueFormatted + " ETH" + (usdStr ? " (" + usdStr + ")" : "");
+        ethValueFormatted +
+        " " +
+        nativeCurrencyByChainId(approvedTx.chainId) +
+        (usdStr ? " (" + usdStr + ")" : "");
 
     showTxFee(approvedTx);
 
@@ -380,20 +396,48 @@ function showTxApproval(details) {
     );
 }
 
+// Whether a personal message is hex by the rule signing reads it with:
+// signing takes getBytes(message), which throws on anything else.
+function isHexMessage(message) {
+    try {
+        getBytes(message);
+        return true;
+    } catch {
+        return false;
+    }
+}
+
+// The text the hex message's bytes decode to as UTF-8, or null when they are
+// not UTF-8. The caller has checked that the message is hex.
 function decodeHexMessage(hex) {
     try {
-        const bytes = Uint8Array.from(
+        return toUtf8String(getBytes(hex));
-            hex
-                .slice(2)
-                .match(/.{1,2}/g)
-                .map((b) => parseInt(b, 16)),
-        );
-        return toUtf8String(bytes);
     } catch {
         return null;
     }
 }
 
+// A character shown as a bordered U+XXXX mark.
+function codePointMark(c) {
+    const code = c.codePointAt(0).toString(16).toUpperCase();
+    return `<span class="border border-border">U+${code.padStart(4, "0")}</span>`;
+}
+
+// The text as HTML, with each character that paints nothing (zero-width and
+// bidirectional characters, variation selectors and Hangul fillers among
+// them), each control character and each line or paragraph separator
+// (U+2028, U+2029) shown as a mark. A line feed is shown as a line break.
+// Left in the text, a paragraph separator would end the byte-order layout
+// for everything after it. The marks are plain ASCII, so the second pass
+// leaves them be.
+function markInvisibleCharacters(text) {
+    return escapeHtml(text)
+        .replace(INVISIBLE_CHARACTERS, codePointMark)
+        .replace(/[\p{Cc}\p{Zl}\p{Zp}]/gu, (c) =>
+            c === "\n" ? "<br>" : codePointMark(c),
+        );
+}
+
 // The type ethers will sign typed data as. ethers does not read the page's
 // `primaryType`: it takes the one struct in `types` that no other struct
 // refers to. Throws when the types name no such single struct, which ethers
@@ -657,15 +701,33 @@ function showSignApproval(details) {
         ? "Typed data (EIP-712)"
         : "Personal message";
 
+    // A personal message is signed as the bytes its hex encodes, so the hex
+    // is shown as well as any text it decodes to, and that text is laid out
+    // left to right in the order of its bytes. Signing reads the bytes from
+    // the hex, so a message that is not hex cannot be signed: it is shown as
+    // the text it is, and refused.
+    let refusal = null;
+    $("approve-sign-hex-section").classList.add("hidden");
+    $("approve-sign-message").classList.toggle("am-byte-order", !isTyped);
     if (isTyped) {
         $("approve-sign-message").innerHTML = formatTypedDataHtml(sp.typedData);
-    } else {
+        refusal = typedDataRefusal(sp);
+    } else if (isHexMessage(sp.message)) {
         const decoded = decodeHexMessage(sp.message);
         if (decoded !== null) {
-            $("approve-sign-message").textContent = decoded;
+            $("approve-sign-message").innerHTML =
+                markInvisibleCharacters(decoded);
         } else {
-            $("approve-sign-message").textContent = sp.message;
+            $("approve-sign-message").textContent = "This message is not text.";
         }
+        $("approve-sign-hex").textContent = sp.message;
+        $("approve-sign-hex-section").classList.remove("hidden");
+    } else {
+        $("approve-sign-message").innerHTML = markInvisibleCharacters(
+            sp.message,
+        );
+        refusal =
+            "This message is plain text, not hex, so it cannot be signed.";
     }
 
     // Display danger warning for eth_sign (raw hash signing)
@@ -687,7 +749,6 @@ function showSignApproval(details) {
 
     showView("approve-sign");
     attachCopyHandlers("view-approve-sign");
-    const refusal = typedDataRefusal(sp);
     if (refusal) {
         showError("approve-sign-error", refusal);
         $("btn-approve-sign").disabled = true;

src/popup/views/confirmTx.js

@@ -11,13 +11,14 @@ const {
     addressTitle,
     escapeHtml,
     displaySymbol,
+    nativeCurrency,
     renderAddressHtml,
     attachCopyHandlers,
     goBack,
     onViewLeave,
     formatFee,
 } = require("./helpers");
-const { state } = require("../../shared/state");
+const { state, currentNetwork } = require("../../shared/state");
 const { getSignerForAddress } = require("../../shared/wallet");
 const { decryptWithPassword } = require("../../shared/vault");
 const { formatUsd, getPrice } = require("../../shared/prices");
@@ -42,6 +43,7 @@ const {
     FEE_UNAVAILABLE,
     feeReserveWei,
     feeEstimateWei,
+    maxEthAmount,
     validateTransfer,
 } = require("../../shared/txValidation");
 const { log } = require("../../shared/log");
@@ -53,6 +55,10 @@ let pendingTx = null;
 // filled in by estimateGas() when the estimate resolves or fails.
 let feeStatus = FEE_PENDING;
 let feeWei = null;
+// The fee fields a max ETH send is signed with: those of the estimate its
+// amount was derived from. Null for any other send, which ethers prices from
+// the node at signing time.
+let maxSendFees = null;
 
 function restore() {
     const d = state.viewData;
@@ -81,16 +87,30 @@ function valueWithUsd(text, usdAmount) {
     return text;
 }
 
+// The Amount line, with its USD value. A max ETH send's line is drawn again
+// once its amount is re-derived from the fee estimate.
+function renderAmount(txInfo) {
+    const isErc20 = txInfo.token !== "ETH";
+    const rawSymbol = isErc20 ? txInfo.tokenSymbol || "?" : nativeCurrency();
+    const price = isErc20 ? getPrice(rawSymbol) : getPrice("ETH");
+    const amountUsd = price ? parseFloat(txInfo.amount) * price : null;
+    $("confirm-amount").textContent = valueWithUsd(
+        txInfo.amount + " " + displaySymbol(rawSymbol),
+        amountUsd,
+    );
+}
+
 function show(txInfo) {
     pendingTx = txInfo;
     feeStatus = FEE_PENDING;
     feeWei = null;
+    maxSendFees = null;
 
     const isErc20 = txInfo.token !== "ETH";
     // The raw symbol is the price-table key; the capped one is what the
     // screen says. Truncating before the lookup would silently drop the
     // price of any token whose symbol is long enough to be capped.
-    const rawSymbol = isErc20 ? txInfo.tokenSymbol || "?" : "ETH";
+    const rawSymbol = isErc20 ? txInfo.tokenSymbol || "?" : nativeCurrency();
     const symbol = displaySymbol(rawSymbol);
 
     // Transaction type
@@ -98,7 +118,7 @@ function show(txInfo) {
         $("confirm-type").textContent =
             "ERC-20 token transfer (" + symbol + ")";
     } else {
-        $("confirm-type").textContent = "Native ETH transfer";
+        $("confirm-type").textContent = "Native " + symbol + " transfer";
     }
 
     // Token contract section (ERC-20 only)
@@ -131,18 +151,11 @@ function show(txInfo) {
     );
     $("confirm-to-ens").classList.add("hidden");
 
-    // Amount (with inline USD)
+    renderAmount(txInfo);
-    const ethPrice = getPrice("ETH");
-    const tokenPrice = getPrice(rawSymbol);
-    const amountNum = parseFloat(txInfo.amount);
-    const price = isErc20 ? tokenPrice : ethPrice;
-    const amountUsd = price ? amountNum * price : null;
-    $("confirm-amount").textContent = valueWithUsd(
-        txInfo.amount + " " + symbol,
-        amountUsd,
-    );
 
     // Balance (with inline USD)
+    const ethPrice = getPrice("ETH");
+    const tokenPrice = getPrice(rawSymbol);
     if (isErc20) {
         // null is a balance whose scale nothing knows, not a balance of zero
         // (https://git.eeqj.de/sneak/AutistMask/issues/349). The send is
@@ -162,7 +175,7 @@ function show(txInfo) {
         const bal = txInfo.balance || "0";
         const balUsd = ethPrice ? parseFloat(bal) * ethPrice : null;
         $("confirm-balance").textContent = valueWithUsd(
-            truncateAmountNeverZero(bal) + " ETH",
+            truncateAmountNeverZero(bal) + " " + symbol,
             balUsd,
         );
     }
@@ -197,6 +210,19 @@ function show(txInfo) {
     // estimate landing later never moves anything.
     $("confirm-amount-fee-error").classList.toggle("hidden", isErc20);
     $("confirm-gas-error").classList.toggle("hidden", !isErc20);
+    $("confirm-gas-error").textContent =
+        "You do not have enough " +
+        nativeCurrency() +
+        " to pay the network fee for this transfer. Please add " +
+        nativeCurrency() +
+        " to this address and try again.";
+
+    // Shown later, once checkRecipientHistory() finds a contract.
+    $("confirm-contract-warning").textContent =
+        "WARNING: The recipient is a smart contract. Sending " +
+        nativeCurrency() +
+        " or tokens directly to a contract may result in permanent loss of" +
+        " funds.";
 
     // The fee-unknown message names its cause, which is also known here.
     // Without the token's scale estimateGas() cannot encode the transfer, so
@@ -245,7 +271,9 @@ function show(txInfo) {
 // touches already occupies its space, so re-running it never moves anything.
 function renderValidation(txInfo) {
     const isErc20 = txInfo.token !== "ETH";
-    const symbol = isErc20 ? displaySymbol(txInfo.tokenSymbol || "?") : "ETH";
+    const symbol = isErc20
+        ? displaySymbol(txInfo.tokenSymbol || "?")
+        : nativeCurrency();
 
     const { canSend, codes } = validateTransfer({
         isErc20,
@@ -258,7 +286,7 @@ function renderValidation(txInfo) {
 
     // Messages carrying the user's own numbers are built here; the fixed
     // sentences live in the reserved elements in index.html, except the
-    // fee-unknown one, which show() sets.
+    // gas and fee-unknown ones, which show() sets.
     const messages = [];
     if (codes.includes(CODES.AMOUNT_INVALID)) {
         messages.push("Please enter a valid amount to send.");
@@ -287,9 +315,13 @@ function renderValidation(txInfo) {
         messages.push(
             "Insufficient balance. You have " +
                 truncateAmountNeverZero(txInfo.balance || "0") +
-                " ETH but are trying to send " +
+                " " +
+                symbol +
+                " but are trying to send " +
                 txInfo.amount +
-                " ETH.",
+                " " +
+                symbol +
+                ".",
         );
     }
 
@@ -360,8 +392,8 @@ async function estimateGas(txInfo) {
         }
 
         // What the node will require to be reserved, which is what the gate
-        // must be: the send pins no fee fields, so it is broadcast as a
+        // must be: the send is broadcast as a type-2 transaction priced at
-        // type-2 transaction priced at maxFeePerGas.
+        // maxFeePerGas, which only a max ETH send pins (see below).
         const gasCostWei = feeReserveWei(gasLimit, feeData);
         if (gasCostWei === null) {
             throw new Error("no usable gas price from the provider");
@@ -378,21 +410,51 @@ async function estimateGas(txInfo) {
         // The fee line goes through formatFee(), as the approval screen's
         // does, so the same fee reads the same on both.
         if (estimateWei !== null && estimateWei < gasCostWei) {
-            $("confirm-fee-amount").textContent = "~" + formatFee(estimateWei);
+            $("confirm-fee-amount").textContent =
+                "~" + formatFee(estimateWei, nativeCurrency());
             $("confirm-fee-reserve").textContent =
                 "up to " +
                 truncateAmountNeverZero(formatEther(gasCostWei)) +
-                " ETH reserved";
+                " " +
+                nativeCurrency() +
+                " reserved";
             setVisible("confirm-fee-reserve", true);
         } else {
             // No spread to report: either there is no estimate, or the node
             // quotes a gas price at or above maxFeePerGas, so the expected
             // cost is not below the reserve. Show the reserve alone.
-            $("confirm-fee-amount").textContent = formatFee(gasCostWei);
+            $("confirm-fee-amount").textContent = formatFee(
+                gasCostWei,
+                nativeCurrency(),
+            );
             setVisible("confirm-fee-reserve", false);
         }
         feeStatus = FEE_KNOWN;
         feeWei = gasCostWei;
+        // A max ETH send is the balance minus this estimate's reserve, not the
+        // Send screen's, and is signed with this estimate's fee fields: fees
+        // fetched again at signing could exceed the reserve it leaves, and the
+        // node would refuse it for want of funds. Where the balance no longer
+        // covers the fee, the amount is left as it is and the balance check
+        // below says so.
+        if (txInfo.max && txInfo.token === "ETH") {
+            const amount = maxEthAmount(txInfo.balance, gasCostWei);
+            if (amount !== null) {
+                txInfo.amount = amount;
+                renderAmount(txInfo);
+                // Priced as feeReserveWei() priced the reserve: maxFeePerGas,
+                // or gasPrice on a network with no type-2 pricing.
+                if (feeData.maxFeePerGas != null) {
+                    maxSendFees = {
+                        gasLimit,
+                        maxFeePerGas: feeData.maxFeePerGas,
+                        maxPriorityFeePerGas: feeData.maxPriorityFeePerGas,
+                    };
+                } else {
+                    maxSendFees = { gasLimit, gasPrice: feeData.gasPrice };
+                }
+            }
+        }
         renderValidation(txInfo);
     } catch (e) {
         log.errorf("gas estimation failed:", e.shortMessage || e.message);
@@ -406,18 +468,19 @@ async function estimateGas(txInfo) {
 }
 
 // Populate the transaction this send describes, enforce the fee bound against
-// the fees that were actually filled in, then sign and broadcast it. The send
+// the fees that were actually filled in, then sign and broadcast it. Apart
-// pins no fee fields, so ethers fills maxFeePerGas and the gas limit from what
+// from a max ETH send, which passes its estimate's fee fields as `fees`, the
-// the configured RPC node answers, with nothing otherwise bounding what a
+// send pins no fee fields, so ethers fills maxFeePerGas and the gas limit from
+// what the configured RPC node answers, with nothing otherwise bounding what a
 // hostile node can set — the dApp path's ceilings never reached this one.
 // Populating before the check is what makes assertWithinCeilings() see the
 // same numbers that would be signed; it throws an ApprovalMismatchError when
 // the product gasLimit × maxFeePerGas is over the bound, which the caller
 // shows in the reserved error area rather than sending.
-async function populateVerifyAndSend(connectedSigner, tx) {
+async function populateVerifyAndSend(connectedSigner, tx, fees = null) {
     let request;
     if (tx.token === "ETH") {
-        request = { to: tx.to, value: parseEther(tx.amount) };
+        request = { to: tx.to, value: parseEther(tx.amount), ...fees };
     } else {
         const contract = new Contract(tx.token, ERC20_ABI, connectedSigner);
         // The contract's decimals() is read to be COMPARED with the scale the
@@ -508,6 +571,10 @@ function init(_ctx) {
         $("btn-confirm-send").disabled = true;
         $("btn-confirm-send").classList.add("text-muted");
 
+        // The network it is sent on. The wait, success and error screens
+        // label its amount by this, not by the network active when they draw.
+        pendingTx.chainId = currentNetwork().chainId;
+
         let tx;
         try {
             const signer = getSignerForAddress(
@@ -518,7 +585,11 @@ function init(_ctx) {
             const provider = getProvider(state.rpcUrl, state.networkId);
             const connectedSigner = signer.connect(provider);
 
-            tx = await populateVerifyAndSend(connectedSigner, pendingTx);
+            tx = await populateVerifyAndSend(
+                connectedSigner,
+                pendingTx,
+                maxSendFees,
+            );
 
             // Best-effort: clear decrypted secret after use.
             // Note: JS strings are immutable; this nulls the reference but

src/popup/views/deleteWallet.js

@@ -12,6 +12,7 @@ const {
     removeWalletFromState,
     broadcastActiveChanged,
 } = require("../../shared/walletDelete");
+const { INVISIBLE_CHARACTERS } = require("../../shared/symbolSpoof");
 
 let deleteWalletIndex = null;
 let lostPasswordIndex = null;
@@ -20,21 +21,31 @@ let ctx = null;
 // The name shown for a wallet, and on the lost-password screen the string
 // the user has to type back. One function so the two cannot disagree: a
 // confirmation that asks for a name other than the one on screen is
-// unusable.
+// unusable. A name that shows nothing at all (only spaces, or only
+// zero-width characters) is replaced by "Wallet N" for the same reason:
+// there would be nothing on screen to type back.
 function displayName(walletIdx) {
     const wallet = state.wallets[walletIdx];
-    return (wallet && wallet.name) || "Wallet " + (walletIdx + 1);
+    const name = wallet && wallet.name;
+    if (name && confirmKey(name)) return name;
+    return "Wallet " + (walletIdx + 1);
 }
 
 // What the typed confirmation and the wallet name are compared as. HTML
 // collapses runs of whitespace when it renders the name, so a wallet named
 // "My  Wallet" with two spaces DISPLAYS as "My Wallet": the user cannot
 // see the second space and cannot type a string that matches the stored
-// name. Comparing collapsed on both sides is what keeps the confirmation
+// name. Characters that paint nothing, such as a zero-width space, are
-// satisfiable, on the one screen whose whole purpose is unwedging a user
+// invisible the same way and are removed first. Comparing this form on
-// who is already stuck. Case and surrounding space go the same way.
+// both sides is what keeps the confirmation satisfiable, on the one screen
+// whose whole purpose is unwedging a user who is already stuck. Case and
+// surrounding space go the same way.
 function confirmKey(name) {
-    return name.trim().replace(/\s+/g, " ").toLowerCase();
+    return name
+        .replace(INVISIBLE_CHARACTERS, "")
+        .trim()
+        .replace(/\s+/g, " ")
+        .toLowerCase();
 }
 
 // Drop the password from the DOM and the wallet selection from the
@@ -174,14 +185,16 @@ function init(_ctx) {
             return;
         }
 
-        // Case, surrounding spaces and repeated inner spaces are not part
+        // Case, surrounding spaces, repeated inner spaces and invisible
-        // of the confirmation; see confirmKey(). This asks whether the
+        // characters are not part of the confirmation; see confirmKey().
-        // user knows which wallet they are on; it is not a secret, and
+        // This asks whether the user knows which wallet they are on; it is
-        // refusing "wallet 2" for "Wallet 2" would only teach the user to
+        // not a secret, and refusing "wallet 2" for "Wallet 2" would only
-        // distrust the control.
+        // teach the user to distrust the control. An empty field is
-        const typed = $("delete-wallet-lost-name-input").value;
+        // refused whatever the wallet is called, so no stored name can
+        // ever be confirmed by typing nothing.
+        const typed = confirmKey($("delete-wallet-lost-name-input").value);
         const expected = displayName(lostPasswordIndex);
-        if (confirmKey(typed) !== confirmKey(expected)) {
+        if (typed === "" || typed !== confirmKey(expected)) {
             $("delete-wallet-lost-flash").textContent =
                 "That is not the name of this wallet. Type " +
                 expected +

src/popup/views/helpers.js

@@ -52,9 +52,8 @@ const VIEWS = [
     "export-privkey",
     "show-phrase",
     // Shown by src/popup/views/stateRecovery.js when the stored profile
-    // cannot be read. It is never reached through showView() — by then the
+    // cannot be read, never by showView() (see there), but listed so that
-    // state singleton this file writes on every navigation refuses to be read
+    // every view-hiding loop covers it.
-    // — but it is listed so that every view-hiding loop covers it.
     "state-recovery",
 ];
 
@@ -85,12 +84,28 @@ function hideError(id) {
     el.style.visibility = "hidden";
 }
 
+// Set when src/popup/index.js passes the recovery screen to showView(), and
+// never cleared. Kept in memory for this popup's life, never in
+// state.currentView, which is saved: a popup opened later must not inherit it.
+let stateRecoveryShown = false;
+
 function showView(name) {
+    // The recovery screen, once up, is never replaced: work still running
+    // when it went up, such as a transaction wait, must not take the user off
+    // it or clear what they exported or typed there
+    // (https://git.eeqj.de/sneak/AutistMask/issues/373).
+    if (stateRecoveryShown) return;
     const leaving = state.currentView;
     if (leaving && leaving !== name) {
         const onLeave = viewLeaveHandlers.get(leaving);
         if (onLeave) onLeave();
     }
+    // Passed here only so the screen it replaces is left like any other;
+    // stateRecovery.show() raises it, and it is never the current view.
+    if (name === "state-recovery") {
+        stateRecoveryShown = true;
+        return;
+    }
     for (const v of VIEWS) {
         const el = document.getElementById(`view-${v}`);
         if (el) {
@@ -252,16 +267,31 @@ function unknownableAmount(balance) {
     return Number.isFinite(n) ? n : null;
 }
 
+// The active network's native token symbol, `ETH` on mainnet and `SepoliaETH`
+// on Sepolia, as src/shared/networks.js names it. The wallet's balances and
+// the Send and confirmation screens, which send on the active network, label a
+// native amount with this; a transaction already made or requested is labelled
+// by its own chain id, through nativeCurrencyByChainId() in networks.js. The
+// "ETH" that state.selectedToken and txInfo.token hold is the native token's
+// id, not its label, and stays "ETH" on every network.
+function nativeCurrency() {
+    return currentNetwork().nativeCurrency;
+}
+
 // A network fee in wei as the confirmation and approval screens both show it:
-// the ETH figure through truncateAmountNeverZero(), then its USD value when the
+// the ETH figure through truncateAmountNeverZero() and labelled `symbol`, the
-// ETH price is known. The USD value is of the exact fee, not of the truncated
+// native currency of the network the fee is paid on, then its USD value when
-// figure.
+// the ETH price is known. The USD value is of the exact fee, not of the
-function formatFee(wei) {
+// truncated figure.
+function formatFee(wei, symbol) {
     const eth = formatEther(wei);
     const ethPrice = getPrice("ETH");
     const usd = ethPrice ? formatUsd(parseFloat(eth) * ethPrice) : "";
     return (
-        truncateAmountNeverZero(eth) + " ETH" + (usd ? " (" + usd + ")" : "")
+        truncateAmountNeverZero(eth) +
+        " " +
+        symbol +
+        (usd ? " (" + usd + ")" : "")
     );
 }
 
@@ -303,7 +333,7 @@ function balanceLine(symbol, amount, price, tokenId) {
 
 function balanceLinesForAddress(addr, trackedTokens, showZero) {
     let html = balanceLine(
-        "ETH",
+        nativeCurrency(),
         parseFloat(addr.balance || "0"),
         getPrice("ETH"),
         "ETH",
@@ -660,6 +690,7 @@ module.exports = {
     balanceLinesForAddress,
     addressHoldsFunds,
     unknownableAmount,
+    nativeCurrency,
     formatFee,
     addressColor,
     addressDotHtml,

src/popup/views/home.js

@@ -10,11 +10,17 @@ const {
     addressTitle,
     escapeHtml,
     displaySymbol,
+    nativeCurrency,
     renderAddressHtml,
     attachCopyHandlers,
     pushCurrentView,
 } = require("./helpers");
-const { state, saveState, currentAddress } = require("../../shared/state");
+const {
+    state,
+    saveState,
+    currentAddress,
+    currentNetwork,
+} = require("../../shared/state");
 const { notify } = require("../../shared/browserApi");
 const {
     updateSendBalance,
@@ -68,7 +74,7 @@ function renderTotalValue() {
         return;
     }
     const ethBal = parseFloat(addr.balance || "0");
-    const ethStr = ethBal.toFixed(4) + " ETH";
+    const ethStr = ethBal.toFixed(4) + " " + nativeCurrency();
     const ethUsd = ethPrice ? " (" + formatUsd(ethBal * ethPrice) + ")" : "";
     el.textContent = ethStr + ethUsd;
 
@@ -182,7 +188,11 @@ async function loadHomeTxs(ctx) {
 
     try {
         const fetches = allAddresses.map((addr) =>
-            fetchRecentTransactions(addr, state.blockscoutUrl),
+            fetchRecentTransactions(
+                addr,
+                state.blockscoutUrl,
+                currentNetwork().chainId,
+            ),
         );
         const results = await Promise.all(fetches);
 

src/popup/views/send.js

@@ -5,6 +5,8 @@ const {
     showFlash,
     addressTitle,
     displaySymbol,
+    escapeHtml,
+    nativeCurrency,
     renderAddressHtml,
     attachCopyHandlers,
     goBack,
@@ -20,10 +22,25 @@ const {
     truncateAmountNeverZero,
     isBelowOneMillionth,
 } = require("../../shared/amountDisplay");
-const { getAddress } = require("ethers");
+const {
+    feeReserveWei,
+    maxEthAmount,
+    maxTokenAmount,
+} = require("../../shared/txValidation");
+const { log } = require("../../shared/log");
+const { getAddress, parseEther } = require("ethers");
 
 const ZERO_ADDRESS = "0x0000000000000000000000000000000000000000";
 
+// Whether the amount field holds what Max filled in. The confirmation screen
+// re-derives a max ETH amount from its own fee estimate; typing in the field
+// makes it an ordinary amount again.
+let amountIsMax = false;
+
+// Counts the times the Send screen has opened, so a Max fee estimate started
+// before it was last opened fills nothing in.
+let sendScreenOpenings = 0;
+
 /**
  * Validate a destination address string.
  * Returns { valid: true } or { valid: false, error: "..." }.
@@ -124,7 +141,7 @@ function updateToValidation() {
 
 function renderSendTokenSelect(addr) {
     const sel = $("send-token");
-    sel.innerHTML = '<option value="ETH">ETH</option>';
+    sel.innerHTML = `<option value="ETH">${escapeHtml(nativeCurrency())}</option>`;
     const fraudSet = new Set(
         (state.fraudContracts || []).map((a) => a.toLowerCase()),
     );
@@ -204,7 +221,8 @@ function updateSendBalance() {
         $("send-balance").textContent =
             "Current balance: " +
             truncateAmountNeverZero(addr.balance || "0") +
-            " ETH";
+            " " +
+            nativeCurrency();
     } else {
         const symbol = resolveSymbol(
             token,
@@ -226,9 +244,102 @@ function updateSendBalance() {
     }
 }
 
+// Fill the amount field with the most the selected holding can send: a
+// token's whole balance (cut to 18 decimal places), or for ETH the exact
+// balance minus the fee reserve the confirmation screen checks against, never
+// the rounded balance the screen shows. Where there is nothing to fill in, a
+// flash message says why.
+async function fillMaxAmount() {
+    const addr = currentAddress();
+    if (!addr) return;
+    const token = state.selectedToken || $("send-token").value;
+
+    if (token !== "ETH") {
+        const bal = tokenBalanceAndDecimals(addr, token).tokenBalance;
+        if (bal == null) {
+            showFlash("This token's balance is unknown.");
+            return;
+        }
+        const amount = maxTokenAmount(bal);
+        if (!(parseFloat(amount) > 0)) {
+            showFlash("This token's balance is zero.");
+            return;
+        }
+        $("send-amount").value = amount;
+        amountIsMax = true;
+        return;
+    }
+
+    // The fee is estimated for this recipient, as the confirmation screen
+    // estimates it: sending to a contract can cost more gas.
+    const to = $("send-to").value.trim();
+    if (!validateToAddress(to).valid) {
+        showFlash("Please enter a recipient address first.");
+        return;
+    }
+    const typed = $("send-amount").value;
+    const opening = sendScreenOpenings;
+    let feeWei = null;
+    try {
+        const provider = getProvider(state.rpcUrl, state.networkId);
+        const [feeData, gasLimit] = await Promise.all([
+            provider.getFeeData(),
+            provider.estimateGas({
+                from: addr.address,
+                to,
+                value: parseEther(addr.balance || "0"),
+            }),
+        ]);
+        feeWei = feeReserveWei(gasLimit, feeData);
+    } catch (e) {
+        log.errorf(
+            "max amount fee estimate failed:",
+            e.shortMessage || e.message,
+        );
+    }
+    // While the estimate was in flight the user left the screen (and perhaps
+    // opened it again), typed an amount, or changed the address, the holding
+    // or the recipient: what they did wins.
+    if (
+        state.currentView !== "send" ||
+        sendScreenOpenings !== opening ||
+        currentAddress()?.address !== addr.address ||
+        (state.selectedToken || $("send-token").value) !== token ||
+        $("send-to").value.trim() !== to ||
+        $("send-amount").value !== typed
+    ) {
+        return;
+    }
+
+    if (feeWei === null) {
+        showFlash("The network fee could not be estimated.");
+        return;
+    }
+    const amount = maxEthAmount(addr.balance, feeWei);
+    if (amount === null) {
+        showFlash("Your balance does not cover the network fee.");
+        return;
+    }
+    $("send-amount").value = amount;
+    amountIsMax = true;
+}
+
 function init(_ctx) {
     ctx = _ctx;
-    $("send-token").addEventListener("change", updateSendBalance);
+    $("send-token").addEventListener("change", () => {
+        // A filled-in maximum is the maximum of the holding it was filled in
+        // for.
+        if (amountIsMax) {
+            $("send-amount").value = "";
+            amountIsMax = false;
+        }
+        updateSendBalance();
+    });
+
+    $("btn-send-max").addEventListener("click", fillMaxAmount);
+    $("send-amount").addEventListener("input", () => {
+        amountIsMax = false;
+    });
 
     // Initial state: disable review button until address is entered
     $("btn-send-review").disabled = true;
@@ -305,6 +416,7 @@ function init(_ctx) {
             tokenSymbol: tokenSymbol,
             tokenBalance: tokenBalance,
             tokenDecimals: tokenDecimals,
+            max: amountIsMax,
         });
     });
 
@@ -315,7 +427,10 @@ function init(_ctx) {
     });
 }
 
+// Called each time the Send screen opens, with its fields cleared.
 function resetSendValidation() {
+    sendScreenOpenings++;
+    amountIsMax = false;
     const errorEl = $("send-to-error");
     const btn = $("btn-send-review");
     if (errorEl) errorEl.textContent = "";

src/popup/views/settings.js

@@ -16,7 +16,12 @@ const {
 } = require("../dustThreshold");
 const { state, saveState, currentNetwork } = require("../../shared/state");
 const { onChainSwitch } = require("../../shared/chainSwitch");
-const { log, debugFetch, setRuntimeDebug } = require("../../shared/log");
+const {
+    log,
+    debugFetch,
+    urlOrigin,
+    setRuntimeDebug,
+} = require("../../shared/log");
 const deleteWallet = require("./deleteWallet");
 const showPhrase = require("./showPhrase");
 const { walletHasRecoveryPhrase } = require("../../shared/wallet");
@@ -272,8 +277,11 @@ function init(ctx) {
                 showFlash("Wrong network: expected " + net.name + ".");
                 return;
             }
-        } catch (e) {
+        } catch {
-            log.errorf("RPC validation fetch failed:", e.message);
+            // Not the error's message: fetch puts the whole URL, password and
+            // key included, in the message of the error it throws for a URL
+            // with a user name and password or one it cannot parse.
+            log.errorf("RPC validation fetch failed:", urlOrigin(url));
             showFlash("Could not reach endpoint.");
             return;
         }
@@ -295,8 +303,9 @@ function init(ctx) {
                 showFlash("Endpoint returned HTTP " + resp.status + ".");
                 return;
             }
-        } catch (e) {
+        } catch {
-            log.errorf("Blockscout validation failed:", e.message);
+            // Not the error's message, as for the RPC check above.
+            log.errorf("Blockscout validation failed:", urlOrigin(url));
             showFlash("Could not reach endpoint.");
             return;
         }

src/popup/views/stateRecovery.js

@@ -3,8 +3,10 @@
 // Everything else in the popup assumes a loaded profile: showView() reads and
 // writes the state singleton, every view renders from it, and the Settings
 // gear leads to a screen that does both. None of that is available here — by
-// the time this runs, loadState() has REFUSED, deliberately, and reading the
+// the time this runs, the stored record has been REFUSED, deliberately: at
-// singleton throws (https://git.eeqj.de/sneak/AutistMask/issues/311).
+// open loadState() refused it and reading the singleton throws
+// (https://git.eeqj.de/sneak/AutistMask/issues/311), and under an open popup
+// a save refused it (https://git.eeqj.de/sneak/AutistMask/issues/373).
 //
 // So this module talks to the DOM directly and touches no state at all. It is
 // the one screen that must work when nothing else can, which is also why it
@@ -170,6 +172,11 @@ function wire() {
  *     refused, or its sentence.
  */
 function show(problem) {
+    // Already up: a later save that trips over the same record, such as a
+    // refresh that was in flight when the screen went up, must not clear what
+    // the user has exported or typed here.
+    if (!$("view-state-recovery").classList.contains("hidden")) return;
+
     const sentence =
         (problem && (problem.problem || problem.message)) || String(problem);
 

src/popup/views/transactionDetail.js

@@ -21,6 +21,7 @@ const {
     goBack,
 } = require("./helpers");
 const { state } = require("../../shared/state");
+const { nativeCurrencyByChainId } = require("../../shared/networks");
 const { formatEther, formatUnits } = require("ethers");
 const makeBlockie = require("ethereum-blockies-base64");
 const { log, debugFetch } = require("../../shared/log");
@@ -41,8 +42,10 @@ function getTransactionType(tx) {
             return "Token Approval";
         return "Contract Call";
     }
-    if (tx.symbol && tx.symbol !== "ETH") return "ERC-20 Token Transfer";
+    // By the token contract, not the symbol: a token chooses its own symbol
-    return "Native ETH Transfer";
+    // and can report the native token's, but only a token transfer has one.
+    if (tx.contractAddress) return "ERC-20 Token Transfer";
+    return "Native " + nativeCurrencyByChainId(tx.chainId) + " Transfer";
 }
 
 function blockieHtml(address) {
@@ -84,6 +87,11 @@ function show(tx) {
             isContractCall: tx.isContractCall || false,
             method: tx.method || null,
             contractAddress: tx.contractAddress || null,
+            // The network the history entry was read from. The type line and
+            // the fee are in its native currency, not the active network's:
+            // a site can switch the active network before a later popup
+            // shows this screen again.
+            chainId: tx.chainId,
         },
     };
     render();
@@ -179,7 +187,7 @@ function render() {
         if (el) el.classList.add("hidden");
     }
 
-    loadFullTxDetails(tx.hash, tx.to);
+    loadFullTxDetails(tx.hash, tx.to, tx.chainId);
 
     const isoStr = isoDate(tx.timestamp);
     $("tx-detail-time").innerHTML =
@@ -197,7 +205,7 @@ function showDetailField(sectionId, contentId, value) {
     section.classList.remove("hidden");
 }
 
-function populateOnChainDetails(txData) {
+function populateOnChainDetails(txData, chainId) {
     // Block number
     if (txData.block_number != null) {
         const blockLink = explorerUrl("block", String(txData.block_number));
@@ -227,7 +235,7 @@ function populateOnChainDetails(txData) {
         showDetailField(
             "tx-detail-fee-section",
             "tx-detail-fee",
-            feeEth + " ETH",
+            feeEth + " " + nativeCurrencyByChainId(chainId),
         );
     }
 
@@ -287,7 +295,7 @@ function populateOnChainDetails(txData) {
     }
 }
 
-async function loadFullTxDetails(txHash, toAddress) {
+async function loadFullTxDetails(txHash, toAddress, chainId) {
     const section = $("tx-detail-calldata-section");
     const actionEl = $("tx-detail-calldata-action");
     const detailsEl = $("tx-detail-calldata-details");
@@ -304,7 +312,7 @@ async function loadFullTxDetails(txHash, toAddress) {
         const txData = await resp.json();
 
         // Populate on-chain detail fields (block, nonce, gas, fee)
-        populateOnChainDetails(txData);
+        populateOnChainDetails(txData, chainId);
 
         const inputData = txData.raw_input || txData.input || null;
         if (!inputData || inputData === "0x") return;

src/popup/views/txStatus.js

@@ -16,6 +16,7 @@ const {
 } = require("./helpers");
 const { resolveTokenSymbol } = require("../../shared/approvalAmount");
 const { state } = require("../../shared/state");
+const { nativeCurrencyByChainId } = require("../../shared/networks");
 const { getProvider } = require("../../shared/balances");
 const { log } = require("../../shared/log");
 
@@ -86,9 +87,13 @@ function startWait(txInfo, txHash, broadcastTime, pollNow) {
     endWait();
     const id = waitId;
 
+    // A native amount, here and on the success and error screens, is in the
+    // native currency of txInfo.chainId, the network the transaction was sent
+    // on, not the active network's: a site can switch the active network
+    // while this screen is open or before a later popup resumes it.
     const symbol =
         txInfo.token === "ETH"
-            ? "ETH"
+            ? nativeCurrencyByChainId(txInfo.chainId)
             : displaySymbol(txInfo.tokenSymbol || "?");
     $("wait-tx-summary").textContent = txInfo.amount + " " + symbol;
     $("wait-tx-to").innerHTML = toAddressHtml(txInfo.to);
@@ -193,9 +198,10 @@ function showWait(txInfo, txHash) {
 // an object merely missing one of them throws a TypeError out of
 // restoreView() — which init() does not guard, skipping the rest of popup
 // init and leaving wait-tx on screen with no back control. A non-numeric
-// broadcastTime leaves an unexitable wait counting "NaNs". txInfo.token and
+// broadcastTime leaves an unexitable wait counting "NaNs". txInfo.token,
-// txInfo.tokenSymbol are deliberately unchecked: they are compared and
+// txInfo.tokenSymbol and txInfo.chainId are deliberately unchecked: they are
-// coalesced rather than dereferenced, and tokenSymbol is null for ETH.
+// compared and coalesced rather than dereferenced, and tokenSymbol is null for
+// ETH.
 function restoreWait() {
     const d = state.viewData;
     if (!d || !d.pendingWait) return false;
@@ -223,7 +229,7 @@ function showSuccess(txInfo, txHash, blockNumber) {
 
     const symbol =
         txInfo.token === "ETH"
-            ? "ETH"
+            ? nativeCurrencyByChainId(txInfo.chainId)
             : displaySymbol(txInfo.tokenSymbol || "?");
     state.viewData = {
         amount: txInfo.amount,
@@ -320,7 +326,7 @@ function showError(txInfo, txHash, message) {
 
     const symbol =
         txInfo.token === "ETH"
-            ? "ETH"
+            ? nativeCurrencyByChainId(txInfo.chainId)
             : displaySymbol(txInfo.tokenSymbol || "?");
     state.viewData = {
         amount: txInfo.amount,

src/shared/approvalAmount.js

@@ -23,11 +23,11 @@
 // disputed is refused rather than guessed at.
 
 // Solidity's decimals() is a uint8, and every source here is ultimately
-// reporting that call's result. toDecimals() is that check, shared with the
+// reporting that call's result. toDecimals() is that check, stopping at the 80
-// send path rather than copied: the bundled list stores numbers, the
+// places formatUnits() accepts, and shared with the send path rather than
-// explorer's copy arrives as a string, and a token the user added by hand
+// copied: the bundled list stores numbers, the explorer's copy arrives as a
-// carries whatever lookupTokenInfo() got back, so the accepted types are
+// string, and a token the user added by hand carries whatever lookupTokenInfo()
-// enumerated rather than coerced.
+// got back, so the accepted types are enumerated rather than coerced.
 const { toDecimals } = require("./transferAmount");
 const { TOKEN_BY_ADDRESS } = require("./tokenList");
 const { isSpoofedSymbol } = require("./symbolSpoof");

src/shared/approvalVerify.js

@@ -54,9 +54,11 @@ const {
     formatEther,
     getAddress,
     getBytes,
+    toQuantity,
     verifyMessage,
     verifyTypedData,
 } = require("ethers");
+const { nativeCurrencyByChainId } = require("./networks");
 
 // The only transaction types this wallet signs: legacy, EIP-2930 and
 // EIP-1559. populateTransaction() produces nothing else, so nothing else can
@@ -407,12 +409,21 @@ function assertWithinCeilings(tx) {
             price = normalizeQuantity(tx.gasPrice, "gas price");
         }
         if (price !== null && gasLimit * price > MAX_TOTAL_FEE) {
+            // The fee is paid in the native currency of the network the
+            // transaction is for. Every caller's transaction names it.
+            const nativeCurrency = nativeCurrencyByChainId(
+                present(tx.chainId) ? toQuantity(tx.chainId) : null,
+            );
             throw refuse(
                 "This transaction would allow a network fee of up to " +
                     formatEther(gasLimit * price) +
-                    " ETH, which is more than the " +
+                    " " +
+                    nativeCurrency +
+                    ", which is more than the " +
                     formatEther(MAX_TOTAL_FEE) +
-                    " ETH this wallet will sign for.",
+                    " " +
+                    nativeCurrency +
+                    " this wallet will sign for.",
             );
         }
     }

src/shared/balances.js

@@ -147,20 +147,20 @@ async function fetchTokenBalances(address, blockscoutUrl, trackedTokens) {
             // null is a holding of an amount that cannot be stated, which is
             // not the same as a holding of zero, and must never render as one.
             const bal = scale === null ? null : formatTokenBalance(raw, scale);
-            // null means the explorer reported no count, which is not the
+            // null means the explorer reported no readable count, which is
-            // same as a count of zero.  This gate is not the low-holder
+            // not the same as a count of zero.  This gate is not the
-            // display filter: it has no user-facing off switch and governs
+            // low-holder display filter: it has no user-facing off switch and
-            // the whole balance list, so it stays strict and admits a token
+            // governs the whole balance list, so it stays strict and admits a
-            // only on a reported count — an unreported one is no evidence.
+            // token only on a reported count — an unreported one is no
-            // A legitimate token still reaches the list through the known
+            // evidence, and `null >= LOW_HOLDER_THRESHOLD` is false.  A
+            // legitimate token still reaches the list through the known
             // token list or by the user tracking it, and the null is carried
             // through to the views, where the two low-holder filters treat
             // an unknown count as "do not judge" rather than as zero.
             const holders = parseHoldersCount(item.token.holders_count);
             const isKnown = TOKEN_BY_ADDRESS.has(tokenAddr);
             const isTracked = trackedSet.has(tokenAddr);
-            const hasEnoughHolders =
+            const hasEnoughHolders = holders >= LOW_HOLDER_THRESHOLD;
-                holders !== null && holders >= LOW_HOLDER_THRESHOLD;
 
             // Skip spam tokens the user never asked to see
             if (!isKnown && !isTracked && !hasEnoughHolders) continue;

src/shared/holders.js

@@ -9,13 +9,22 @@
 
 const LOW_HOLDER_THRESHOLD = 1000;
 
-// Parse an explorer-supplied holders_count into a number, or null when the
+// Parse an explorer-supplied holders_count into a number, or null when it is
-// explorer did not report one.  Anything unparseable is unknown too: a count
+// not one.  Only a whole number of zero or more, or a string made of nothing
-// we cannot read is not a count of zero.
+// but the digits 0-9, is a count.  Anything else is null, never read in part:
+// "1,000", "0x10" and "1e3" are unknown, not 1, 0 and 1, because a count we
+// cannot read is not a low count.  A count above Number.MAX_SAFE_INTEGER is
+// null too: a number cannot hold it exactly, so it would come back rounded,
+// or as Infinity.
 function parseHoldersCount(raw) {
-    if (raw === null || raw === undefined || raw === "") return null;
+    if (typeof raw === "number") {
-    const n = parseInt(raw, 10);
+        return Number.isSafeInteger(raw) && raw >= 0 ? raw : null;
-    return Number.isFinite(n) ? n : null;
+    }
+    if (typeof raw === "string" && /^[0-9]+$/.test(raw)) {
+        const count = Number(raw);
+        return Number.isSafeInteger(count) ? count : null;
+    }
+    return null;
 }
 
 // True only for a token the explorer reported as having fewer holders than

src/shared/log.js

@@ -43,7 +43,8 @@ const log = {
 };
 
 // The origin (scheme, host and port) of a URL, for logging in place of the
-// URL: RPC providers put API keys in the path or the query string. A URL that
+// URL: RPC providers put API keys in the path or the query string, and a URL
+// can carry a user name and password, which the origin leaves out. A URL that
 // does not parse gives "", so logging never stops a request.
 function urlOrigin(url) {
     try {

src/shared/networks.js

@@ -76,6 +76,15 @@ function networkByChainId(chainId) {
     return null;
 }
 
+// The native currency of the network with this chain id. A transaction's
+// value and fee are labelled with the one of the chain the transaction is on,
+// which need not be the active network. `ETH` when the chain id is missing or
+// no network here has it.
+function nativeCurrencyByChainId(chainId) {
+    const network = networkByChainId(chainId);
+    return network ? network.nativeCurrency : "ETH";
+}
+
 // Build a block explorer link for the given path type and value.
 // type: "address" | "tx" | "token" | "block"
 function explorerLink(network, type, value) {
@@ -89,5 +98,6 @@ module.exports = {
     isKnownNetworkId,
     networkById,
     networkByChainId,
+    nativeCurrencyByChainId,
     explorerLink,
 };

src/shared/state.js

@@ -122,9 +122,9 @@ function currentNetwork() {
     return networkById(state.networkId);
 }
 
-// The persisted fields as they stood at the end of this page's last
+// The persisted fields as this page held them when its last loadState()
-// loadState() or saveState(). saveState() diffs the live state against this
+// finished, or when its last successful saveState() began. saveState() diffs
-// to find only the fields THIS page actually changed.
+// the live state against this to find only the fields THIS page changed since.
 //
 // Deep-cloned, not a reference: callers mutate persisted objects and arrays
 // in place (state.wallets.push(...)), and a reference baseline would mutate
@@ -464,7 +464,10 @@ function mergeNetworkEndpoints(base, ours, theirs) {
 // does not own goes on being whatever its last loadState() saw, same as
 // before this fix; only the persisted record is guaranteed current.
 async function saveStateOnce() {
-    const current = snapshotPersisted();
+    // A copy, so what this save compares and writes is the page's state as it
+    // stood when the save began. A change made while it waits on storage is
+    // left for the next save, which compares against this copy.
+    const current = structuredClone(snapshotPersisted());
     const result = await storageGet("autistmask");
     // The record in storage right now is about to be merged into and written
     // back, so it is validated exactly like a load validates it. Without this,
@@ -521,7 +524,11 @@ async function saveStateOnce() {
     // exactly as it stood; see the note above.
     rawState.hasWallet = rawState.wallets.length > 0;
 
-    baseline = structuredClone(snapshotPersisted());
+    // What this save compared and wrote, not the page's state now: a change
+    // made during the save must still differ from the baseline, or the save
+    // queued after it finds nothing to store
+    // (https://git.eeqj.de/sneak/AutistMask/issues/448).
+    baseline = current;
 }
 
 // showView() calls saveState() on every navigation without awaiting it, so

src/shared/symbolSpoof.js

@@ -11,8 +11,8 @@
 // KNOWN_SYMBOLS maps a symbol to the set of lowercased contract addresses
 // that may bear it, or to null.  Null means the symbol belongs to the native
 // asset, which has no contract at all, so no contract may bear it and every
-// one that does is a spoof.  "ETH" is the only such entry today; the rule is
+// one that does is a spoof.  "ETH" is one such entry, and every network's
-// written so that a second one needs no change here or at any call site.
+// `nativeCurrency` in networks.js (`SepoliaETH`) is another, on every network.
 //
 // The value is a set because a ticker is not unique: seven symbols in the
 // bundled list belong to two real contracts each, and answering with one of
@@ -34,6 +34,11 @@ function normalizeAddress(addr) {
     return (addr || "").toLowerCase();
 }
 
+// The characters that paint nothing; normalizeSymbol below says which they
+// are. The signature screen marks them in a personal message
+// (src/popup/views/approval.js).
+const INVISIBLE_CHARACTERS = /[\p{Cf}\p{Default_Ignorable_Code_Point}\x7F]/gu;
+
 // Fold a symbol onto what a user actually sees, and no further:
 //
 //   NFKC        collapses compatibility variants that render as the ASCII
@@ -82,7 +87,7 @@ function normalizeAddress(addr) {
 function normalizeSymbol(symbol) {
     return String(symbol || "")
         .normalize("NFKC")
-        .replace(/[\p{Cf}\p{Default_Ignorable_Code_Point}\x7F]/gu, "")
+        .replace(INVISIBLE_CHARACTERS, "")
         .trim()
         .toUpperCase();
 }
@@ -104,5 +109,6 @@ function isSpoofedSymbol(symbol, contractAddress) {
 }
 
 module.exports = {
+    INVISIBLE_CHARACTERS,
     isSpoofedSymbol,
 };

src/shared/tokenList.js

@@ -6,6 +6,7 @@
 // 511 tokens.
 
 const { debugFetch } = require("./log");
+const { NETWORKS } = require("./networks");
 
 const COINDESK_API = "https://data-api.coindesk.com/index/cc/v1/latest/tick";
 
@@ -3610,7 +3611,9 @@ for (const t of TOKENS) {
 // Build a map of symbol (uppercased) -> the set of contract addresses
 // (lowercased) that legitimately bear it.  Used for spoofed-symbol detection.
 // "ETH" maps to null: the native asset has no contract, so no contract may
-// bear its symbol.
+// bear its symbol. So does every network's `nativeCurrency` in networks.js
+// (`SepoliaETH`), on every network, since that is the label the wallet shows
+// its native asset under on that network.
 //
 // The value is a set and not a single address because tickers are not unique
 // and the list above proves it: seven of these 512 tokens share a symbol with
@@ -3624,6 +3627,9 @@ for (const t of TOKENS) {
 // loosen the rule, because a contract outside the set is still a spoof.
 const KNOWN_SYMBOLS = new Map();
 KNOWN_SYMBOLS.set("ETH", null);
+for (const network of Object.values(NETWORKS)) {
+    KNOWN_SYMBOLS.set(network.nativeCurrency.toUpperCase(), null);
+}
 for (const t of TOKENS) {
     const upper = t.symbol.toUpperCase();
     if (!KNOWN_SYMBOLS.has(upper)) {

src/shared/transactions.js

@@ -11,6 +11,7 @@ const { log, debugFetch } = require("./log");
 const { TOKEN_BY_ADDRESS } = require("./tokenList");
 const { parseHoldersCount, isLowHolderCount } = require("./holders");
 const { isSpoofedSymbol } = require("./symbolSpoof");
+const { nativeCurrencyByChainId } = require("./networks");
 // The uint8 test every scale in this wallet goes through. Shared, not copied:
 // a scale is either reported or it is unknown, and "unknown" must mean the
 // same thing here as it does on the screens that refuse to format one.
@@ -28,7 +29,7 @@ function normalizeAddress(addr) {
     return (addr || "").toLowerCase();
 }
 
-function parseTx(tx, addrLower) {
+function parseTx(tx, addrLower, chainId) {
     const from = tx.from?.hash || "";
     const to = tx.to?.hash || "";
     const rawWei = tx.value || "0";
@@ -36,7 +37,7 @@ function parseTx(tx, addrLower) {
     const method = tx.method || null;
 
     // For contract calls, produce a meaningful label instead of "0.0000 ETH"
-    let symbol = "ETH";
+    let symbol = nativeCurrencyByChainId(chainId);
     let value = formatTxValue(formatEther(rawWei));
     let exactValue = formatEther(rawWei);
     let rawAmount = rawWei;
@@ -90,10 +91,11 @@ function parseTx(tx, addrLower) {
         holders: null,
         isContractCall: toIsContract,
         method: method,
+        chainId: chainId,
     };
 }
 
-function parseTokenTransfer(tt, addrLower) {
+function parseTokenTransfer(tt, addrLower, chainId) {
     const from = tt.from?.hash || "";
     const to = tt.to?.hash || "";
     // The explorer's own answer, or null. Never a default: a transfer of
@@ -135,10 +137,12 @@ function parseTokenTransfer(tt, addrLower) {
         contractAddress: normalizeAddress(
             tt.token?.address_hash || tt.token?.address || "",
         ),
-        // null when the explorer reported no count: unknown, not zero.  The
+        // null when the explorer reported no readable count: unknown, not
-        // low-holder filter declines to judge a null, so a legitimate token
+        // zero.  The low-holder filter declines to judge a null, so a
-        // is not hidden because a field went missing upstream.
+        // legitimate token is not hidden because a field went missing
+        // upstream.
         holders: parseHoldersCount(tt.token?.holders_count),
+        chainId: chainId,
     };
 }
 
@@ -221,7 +225,15 @@ function mergeTransactions(txs, tokenTransfers) {
     return merged;
 }
 
-async function fetchRecentTransactions(address, blockscoutUrl, count = 25) {
+// `chainId` is the chain id of the network `blockscoutUrl` serves. Every entry
+// carries it, and a native entry is labelled with that network's
+// `nativeCurrency` from networks.js (`ETH`, `SepoliaETH`).
+async function fetchRecentTransactions(
+    address,
+    blockscoutUrl,
+    chainId,
+    count = 25,
+) {
     log.debugf("fetchRecentTransactions", address);
     const addrLower = normalizeAddress(address);
 
@@ -254,8 +266,10 @@ async function fetchRecentTransactions(address, blockscoutUrl, count = 25) {
     const ttJson = ttResp.ok ? await ttResp.json() : {};
 
     const txs = mergeTransactions(
-        (txJson.items || []).map((tx) => parseTx(tx, addrLower)),
+        (txJson.items || []).map((tx) => parseTx(tx, addrLower, chainId)),
-        (ttJson.items || []).map((tt) => parseTokenTransfer(tt, addrLower)),
+        (ttJson.items || []).map((tt) =>
+            parseTokenTransfer(tt, addrLower, chainId),
+        ),
     );
 
     const result = txs.slice(0, count);

src/shared/transferAmount.js

@@ -27,9 +27,11 @@
 
 const { parseUnits } = require("ethers");
 
-// Solidity's decimals() returns a uint8, so anything outside that range is not
+// Solidity's decimals() returns a uint8, but ethers' formatUnits() and
-// an answer this wallet can use.
+// parseUnits() refuse more than 80 decimal places ("invalid FixedNumber
-const MAX_DECIMALS = 255;
+// decimals (too large)"). A scale of 81 to 255 can be neither displayed nor
+// encoded, so it is not an answer this wallet can use, the same as no answer.
+const MAX_DECIMALS = 80;
 
 const UNKNOWN_DISPLAYED_DECIMALS_MESSAGE =
     "The transfer was not sent, because the number of decimal places this" +
@@ -55,7 +57,7 @@ function mismatchMessage(displayed, onChain) {
 // A decimals value from any source as a number, or null if it is not one.
 // decimals() comes back from ethers as a bigint and the explorer's copy arrives
 // as a string, so both of those are accepted alongside a plain number; anything
-// fractional, negative, out of uint8 range, or of any other type at all is not.
+// fractional, negative, above MAX_DECIMALS, or of any other type at all is not.
 //
 // The types are enumerated rather than coerced because Number() is far too
 // willing: Number([]) is 0 and Number(true) is 1, so a coercing check would

src/shared/txValidation.js

@@ -1,4 +1,4 @@
-// Balance arithmetic for the transaction confirmation screen.
+// Balance arithmetic for the Send and transaction confirmation screens.
 //
 // Pure: no DOM, no network, no state. Everything is exact integer math on
 // 18-decimal fixed point (wei for ETH), so it can be unit tested directly
@@ -10,7 +10,7 @@
 // the token balance arrive as human decimal strings, so comparing them at a
 // common scale is exact.
 
-const { parseUnits } = require("ethers");
+const { parseUnits, formatEther } = require("ethers");
 
 const SCALE_DECIMALS = 18;
 
@@ -87,6 +87,28 @@ function toFixedPoint(value) {
     }
 }
 
+// The most ETH a send can carry: the exact balance minus the fee reserve from
+// feeReserveWei(), as a decimal string, so validateTransfer() passes it with
+// exactly that reserve left behind. `ethBalance` is the exact decimal string
+// balances.js stores, never a rounded one. Null when the balance does not
+// leave anything to send once the fee is paid, or when either input is
+// unusable.
+function maxEthAmount(ethBalance, feeWei) {
+    const balanceWei = toFixedPoint(ethBalance);
+    if (balanceWei === null) return null;
+    if (typeof feeWei !== "bigint" || feeWei < 0n) return null;
+    const amountWei = balanceWei - feeWei;
+    if (amountWei <= 0n) return null;
+    return formatEther(amountWei);
+}
+
+// The most of a token a send can carry: its balance cut down, never rounded
+// up, to the 18 places (SCALE_DECIMALS) an amount may have. A token can
+// declare more than 18 decimals, and its balance is stored with all of them.
+function maxTokenAmount(tokenBalance) {
+    return tokenBalance.replace(/(\.\d{18})\d+$/, "$1");
+}
+
 // Validate a pending transfer against the balances that must cover it.
 //
 //   isErc20      — token transfer rather than a native ETH transfer
@@ -139,13 +161,12 @@ function validateTransfer({
     const feeFp = known ? feeWei : null;
 
     if (isErc20) {
-        // A token can declare more than 18 decimals, and its balance is
+        // Only the first 18 places of the balance are read: an amount with
-        // stored with all of them. Only the first 18 places (SCALE_DECIMALS)
+        // more was refused above, so the places after them cannot decide
-        // are read: an amount with more was refused above, so the places
+        // whether the amount fits.
-        // after them cannot decide whether the amount fits.
         const tokenText =
             typeof tokenBalance === "string"
-                ? tokenBalance.replace(/(\.\d{18})\d+$/, "$1")
+                ? maxTokenAmount(tokenBalance)
                 : tokenBalance;
         const tokenFp = toFixedPoint(tokenText) ?? 0n;
         if (amountFp > tokenFp) codes.push(CODES.INSUFFICIENT_TOKEN);
@@ -174,6 +195,8 @@ module.exports = {
     SCALE_DECIMALS,
     feeReserveWei,
     feeEstimateWei,
+    maxEthAmount,
+    maxTokenAmount,
     toFixedPoint,
     validateTransfer,
 };

src/shared/uniswap.js

@@ -84,17 +84,31 @@ function present(value) {
 //
 // `amountOutMinimum` gets no such mapping: V4Router compares it directly
 // (`if (amountOut < params.amountOutMinimum) revert V4TooLittleReceived`), so
-// a zero minimum is a literal zero slippage floor and is stated as one. Nor do
+// a zero minimum is a literal zero slippage floor and is stated as one. Nor
-// the V2/V3 paths have it — universal-router's `V3SwapRouter.v3SwapExactInput`
+// does the V3 path have it — universal-router's `V3SwapRouter.v3SwapExactInput`
 // special-cases only `ActionConstants.CONTRACT_BALANCE` (1<<255), never zero —
-// so a zero `amountIn` there is a literal zero and is displayed as one.
+// so a zero V3 `amountIn` is a literal zero and is displayed as one. The V2
+// exact-in path gives zero a meaning of its own: see ALREADY_PAID.
 const OPEN_DELTA = Symbol("v4-open-delta");
 
-// The two amount lines that state a fact instead of a quantity. Same register
+// The Universal Router's V2 exact-in spells "the pair already holds the input
-// as UNNAMED_CURRENCY — a sentence in the value slot, so it cannot be misread
+// tokens" as an amount of zero: universal-router
-// as a number — and deliberately not a third phrasing of "not named": these
+// `contracts/libraries/Constants.sol` declares
-// say different things.
+// `uint256 internal constant ALREADY_PAID = 0` ("Used for identifying cases
+// when a v2 pair has already received input tokens"), and
+// `V2SwapRouter.v2SwapExactInput` makes no payment of its own when `amountIn`
+// equals it. The swap then spends whatever an earlier step sent to the pair.
+// As with OPEN_DELTA, the calldata states no quantity, and "0.0000" would say
+// that nothing is swapped.
+const ALREADY_PAID = Symbol("v2-already-paid");
+
+// The amount lines that state a fact instead of a quantity. Same register as
+// UNNAMED_CURRENCY — a sentence in the value slot, so it cannot be misread as a
+// number — and deliberately not another phrasing of "not named": these say
+// different things.
 const OPEN_DELTA_AMOUNT = "All available (V4 open delta)";
+const ALREADY_PAID_AMOUNT =
+    "Whatever an earlier step sent to the pair (V2 already paid)";
 const NO_MINIMUM = "None (no minimum guaranteed)";
 
 // Permit2 amounts are uint160; the maximum is Permit2's "unbounded".
@@ -185,6 +199,7 @@ function decodeBalanceCheck(input) {
 // Decode V2_SWAP_EXACT_IN (command 0x08) input bytes.
 // ABI: (address recipient, uint256 amountIn, uint256 amountOutMin,
 //        address[] path, bool payerIsUser)
+// A zero `amountIn` is read the way the router reads it, as ALREADY_PAID.
 function decodeV2SwapExactIn(input) {
     try {
         const d = coder.decode(
@@ -192,7 +207,7 @@ function decodeV2SwapExactIn(input) {
             input,
         );
         return {
-            amountIn: d[1],
+            amountIn: d[1] === 0n ? ALREADY_PAID : d[1],
             amountOutMin: d[2],
             tokenIn: d[3][0],
             tokenOut: d[3][d[3].length - 1],
@@ -502,7 +517,13 @@ function decode(data, toAddress, sources) {
 
                 if (cmdId === 0x0e) {
                     const b = decodeBalanceCheck(inputs[i]);
-                    if (b) setOutput(b.token, b.minBalance);
+                    // The router passes this check whenever the owner holds at
+                    // least minBalance, so a zero one guarantees nothing and
+                    // does not replace a minimum an earlier step stated. Any
+                    // other minBalance sets the output side as a swap does.
+                    if (b && !(b.minBalance === 0n && present(minOutput))) {
+                        setOutput(b.token, b.minBalance);
+                    }
                 }
 
                 if (cmdId === 0x00) {
@@ -623,14 +644,20 @@ function decode(data, toAddress, sources) {
         }
 
         if (present(inputAmount)) {
-            // Two amounts need no scale to describe and are named rather than
+            // Three amounts need no scale to describe and are named rather
-            // formatted: V4's open delta, which is not a quantity at all (see
+            // than formatted: V4's open delta and V2's already-paid zero,
-            // OPEN_DELTA), and an unbounded permit. The open-delta test comes
+            // neither of which is a quantity at all (see OPEN_DELTA and
-            // first — the sentinel is not a bigint and cannot be compared with
+            // ALREADY_PAID), and an unbounded permit. Those two tests come
-            // one.
+            // first — the sentinels are not bigints and cannot be compared
+            // with one.
             let amount;
             if (inputAmount === OPEN_DELTA) {
                 amount = { raw: OPEN_DELTA_AMOUNT, display: OPEN_DELTA_AMOUNT };
+            } else if (inputAmount === ALREADY_PAID) {
+                amount = {
+                    raw: ALREADY_PAID_AMOUNT,
+                    display: ALREADY_PAID_AMOUNT,
+                };
             } else if (inputAmount >= MAX_UINT160) {
                 amount = { raw: "Unlimited", display: "Unlimited" };
             } else if (hasV2ExactOut) {
@@ -697,10 +724,15 @@ function decode(data, toAddress, sources) {
 
         details.push({ label: "Steps", value: commandNames.join(" \u2192 ") });
 
+        // A JavaScript date reaches only to 275760-09-13 00:00:00 UTC. A
+        // later deadline, such as the uint256 maximum, makes an invalid date,
+        // and toISOString() throws on one, so that deadline is said in words.
         const deadlineDate = new Date(Number(deadline) * 1000);
         details.push({
             label: "Deadline",
-            value: deadlineDate.toISOString().replace("T", " ").slice(0, 19),
+            value: isNaN(deadlineDate.getTime())
+                ? "After 275760-09-13 00:00:00 (no deadline in practice)"
+                : deadlineDate.toISOString().replace("T", " ").slice(0, 19),
         });
 
         return {

tests/approvalAmount.test.js

@@ -31,11 +31,15 @@ const iface = new Interface(ERC20_ABI);
 const NOVEL_TOKEN = "0xE2E0000000000000000000000000000000000E2e";
 // In the bundled list, at 6 decimals.
 const USDC = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48";
+// In the bundled list, at 0 decimals.
+const SLP = "0xCC8Fa225D80b9c7D42F96e9570156c65D6cAAa25";
 const RECIPIENT = "0xC0FfEE0000000000000000000000000000c0fFEe";
 const SPENDER = "0x1111111111111111111111111111111111111111";
 
 // 5,000 units of a 6-decimal token, the amount from the issue.
 const FIVE_THOUSAND_AT_SIX = 5000000000n;
+// 5,000 units of a 0-decimal token, which are 5,000 tokens.
+const FIVE_THOUSAND_AT_ZERO = 5000n;
 const MAX_UINT256 = (1n << 256n) - 1n;
 
 function transferData(amount) {
@@ -113,6 +117,21 @@ describe("resolveTokenDecimals", () => {
         expect(resolveTokenDecimals(NOVEL_TOKEN, state)).toBe(6);
     });
 
+    // Zero decimals is a real scale, not a missing one, so a source that
+    // answers 0 is used rather than fallen past like the unusable entry above.
+    test("uses a bundled scale of zero", () => {
+        state.trackedTokens = [{ address: SLP, symbol: "SLP", decimals: 18 }];
+        expect(resolveTokenDecimals(SLP, state)).toBe(0);
+    });
+
+    test("uses a tracked scale of zero", () => {
+        state.trackedTokens = [
+            { address: NOVEL_TOKEN, symbol: "NOVEL", decimals: 0 },
+        ];
+        state.wallets = walletsHolding(NOVEL_TOKEN, 18);
+        expect(resolveTokenDecimals(NOVEL_TOKEN, state)).toBe(0);
+    });
+
     test("refuses a scale the explorer's own entries disagree about", () => {
         const wallets = walletsHolding(NOVEL_TOKEN, 6);
         wallets[0].addresses.push({
@@ -184,6 +203,22 @@ describe("decodeCalldata amount", () => {
         expect(line).not.toMatch(/0\.0000/);
     });
 
+    // A token added by hand carries whatever its decimals() returned, and a
+    // uint8 reaches 255, but formatUnits() throws above 80. The throw left the
+    // call undecoded rather than refused
+    // (https://git.eeqj.de/sneak/AutistMask/issues/350).
+    test("a token reporting more than 80 decimals shows base units", () => {
+        state.trackedTokens = [
+            { address: NOVEL_TOKEN, symbol: "NOVEL", decimals: 81 },
+        ];
+        expect(
+            amountLine(transferData(FIVE_THOUSAND_AT_SIX), NOVEL_TOKEN),
+        ).toBe("5000000000 base units (decimals unknown)");
+        expect(amountLine(approveData(FIVE_THOUSAND_AT_SIX), NOVEL_TOKEN)).toBe(
+            "5000000000 base units (decimals unknown)",
+        );
+    });
+
     test("an unbounded allowance is still named, with or without a scale", () => {
         expect(amountLine(approveData(MAX_UINT256), NOVEL_TOKEN)).toBe(
             "Unlimited",
@@ -197,6 +232,21 @@ describe("decodeCalldata amount", () => {
         );
     });
 
+    test("a bundled token with zero decimals shows the true quantity", () => {
+        expect(amountLine(transferData(FIVE_THOUSAND_AT_ZERO), SLP)).toBe(
+            "5000.0000 SLP",
+        );
+    });
+
+    test("a tracked token with zero decimals shows the true quantity", () => {
+        state.trackedTokens = [
+            { address: NOVEL_TOKEN, symbol: "NOVEL", decimals: 0 },
+        ];
+        expect(
+            amountLine(transferData(FIVE_THOUSAND_AT_ZERO), NOVEL_TOKEN),
+        ).toBe("5000.0000 NOVEL");
+    });
+
     test("the amount carried to the status screens is the same string", () => {
         const decoded = decodeCalldata(
             transferData(FIVE_THOUSAND_AT_SIX),

tests/approvalVerify.test.js

@@ -599,6 +599,24 @@ describe("verifySignedTx field comparison", () => {
                 expect(e.message).toContain("1.0 ETH");
             }
         });
+
+        // The fee is in the native currency of the network the transaction is
+        // for, whether its chain id is the hex string the background prepares
+        // or the number ethers parses from a signed transaction.
+        test.each([
+            ["0x1", "ETH"],
+            [1n, "ETH"],
+            ["0xaa36a7", "SepoliaETH"],
+            [11155111n, "SepoliaETH"],
+        ])("the refusal on chain %p names %s", (chainId, nativeCurrency) => {
+            expect(() => assertWithinCeilings({ ...OVER, chainId })).toThrow(
+                "up to 3000.0 " +
+                    nativeCurrency +
+                    ", which is more than the 1.0 " +
+                    nativeCurrency +
+                    " this wallet",
+            );
+        });
     });
 
     test("every field mismatch is a refusal, not a warning", async () => {

tests/backgroundApproval.test.js

@@ -2235,6 +2235,27 @@ describe("a site connection decided as the popup closes", () => {
         });
     });
 
+    // The prompt is decided before the toolbar popup raised for it has
+    // loaded; that popup is torn down and openPopup() rejects only after.
+    test("a toolbar prompt already decided opens no window when openPopup() rejects", async () => {
+        const bg = loadBackground({ actionPopup: true });
+        const opening = deferred();
+        bg.openPopup.mockImplementation(() => opening.promise);
+        const pending = bg.requestSite();
+        await settle();
+
+        const port = bg.connectApproval(pending.id());
+        port.decide(true, false);
+        port.disconnect();
+        await settle();
+        expect(pending.result()).toEqual({ result: [signer.address] });
+
+        opening.reject(new Error("the toolbar popup closed before it loaded"));
+        await settle();
+
+        expect(bg.created).toHaveLength(0);
+    });
+
     // The port carries a decision now, so it carries the sender check the
     // one-off message used to carry. A content script that guessed an
     // approval id must not be able to connect the site it is running on.

tests/debugFetch.test.js

@@ -7,7 +7,7 @@
 // HTTP method, the URL's origin and the JSON-RPC method, and nothing else of
 // the request.
 
-const { debugFetch, setRuntimeDebug } = require("../src/shared/log");
+const { debugFetch, urlOrigin, setRuntimeDebug } = require("../src/shared/log");
 
 const realFetch = globalThis.fetch;
 
@@ -42,3 +42,12 @@ test("logs the origin and JSON-RPC method, not the key in the URL", async () =>
     expect(logged).toContain("https://rpc.example.invalid");
     expect(logged).toContain("eth_chainId");
 });
+
+test("the origin leaves out a user name and password in the URL", () => {
+    expect(
+        urlOrigin("https://user:SECRETPASS@rpc.example.invalid/v3/KEY"),
+    ).toBe("https://rpc.example.invalid");
+    expect(urlOrigin("wss://user:SECRETPASS@rpc.example.invalid:8546/")).toBe(
+        "wss://rpc.example.invalid:8546",
+    );
+});

tests/deleteWalletLostPassword.test.js

@@ -46,6 +46,9 @@ const A1 = "0xdAC17F958D2ee523a2206206994597C13D831ec7";
 const B0 = "0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599";
 const C0 = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48";
 
+// U+200B, built from its code point so that it can be seen in this file.
+const ZERO_WIDTH_SPACE = String.fromCodePoint(0x200b);
+
 // ------------------------------------------------------------ DOM stub
 
 function makeElement(id) {
@@ -342,6 +345,72 @@ describe("the typed confirmation", () => {
             "secret-three",
         ]);
     });
+
+    // A name of only spaces compares as nothing, and so does an empty
+    // field. Typing nothing must still delete nothing.
+    test.each(["", "   "])(
+        "typing %j deletes nothing when the name is only spaces",
+        async (typedValue) => {
+            const { deleteWallet, state, storage } = load();
+            state.wallets[1].name = "   ";
+            await openLostPassword(deleteWallet, 1);
+
+            node("delete-wallet-lost-name-input").value = typedValue;
+            await click("btn-delete-wallet-lost-confirm");
+
+            expect(node("delete-wallet-lost-flash").style.visibility).toBe(
+                "visible",
+            );
+            expect(state.wallets).toHaveLength(3);
+            expect(await persistedWallets(storage)).toHaveLength(3);
+        },
+    );
+
+    // A name that shows nothing would leave nothing on screen to type
+    // back, so the screen names the wallet by its position instead, and
+    // that is what the user types.
+    test.each([
+        ["spaces", "   "],
+        ["a zero-width space", ZERO_WIDTH_SPACE],
+    ])(
+        "a name of only %s is shown and typed back as Wallet 2",
+        async (_label, storedName) => {
+            const { deleteWallet, state, storage } = load();
+            state.wallets[1].name = storedName;
+            await openLostPassword(deleteWallet, 1);
+
+            expect(node("delete-wallet-lost-name").textContent).toBe(
+                "Wallet 2",
+            );
+            node("delete-wallet-lost-name-input").value = "Wallet 2";
+            await click("btn-delete-wallet-lost-confirm");
+
+            const persisted = await persistedWallets(storage);
+            expect(persisted.map((w) => w.encryptedSecret)).toEqual([
+                "secret-one",
+                "secret-three",
+            ]);
+        },
+    );
+
+    // A zero-width space paints nothing, so "My", a zero-width space and
+    // "Wallet" reads as "MyWallet", and that is all the user can type. HTML
+    // does not collapse it the way it collapses spaces, so it has to be
+    // removed explicitly.
+    test("a zero-width space inside the name is not part of it", async () => {
+        const { deleteWallet, state, storage } = load();
+        state.wallets[1].name = "My" + ZERO_WIDTH_SPACE + "Wallet";
+        await openLostPassword(deleteWallet, 1);
+
+        node("delete-wallet-lost-name-input").value = "MyWallet";
+        await click("btn-delete-wallet-lost-confirm");
+
+        const persisted = await persistedWallets(storage);
+        expect(persisted.map((w) => w.encryptedSecret)).toEqual([
+            "secret-one",
+            "secret-three",
+        ]);
+    });
 });
 
 describe("deleting without the password", () => {

tests/e2e/run.js

@@ -204,40 +204,51 @@ async function goHome(page) {
     await visible(page, "#view-main");
 }
 
-// The navigation stack as it was actually persisted, read out of extension
+// One field of the popup's state as it was actually persisted, read out of
-// storage rather than inferred from which screen is showing. A stale entry
+// extension storage rather than inferred from what is on screen.
-// left behind by a forward navigation that threw is invisible on screen
+function persistedField(page, field) {
-// until the user presses Back one time too many — which is exactly the
-// second-order damage #150 did — so the stack itself is what gets asserted.
-function persistedViewStack(page) {
     return page.evaluate(
-        () =>
+        (key) =>
             new Promise((resolve) => {
                 chrome.storage.local.get("autistmask", (r) => {
-                    resolve((r.autistmask && r.autistmask.viewStack) || []);
+                    resolve(r.autistmask ? r.autistmask[key] : undefined);
                 });
             }),
+        field,
     );
 }
 
-// saveState() is fired from showView() without being awaited, so the write
+// The navigation stack as it was actually persisted. A stale entry left
-// lands shortly after the screen does. Polling for the expected stack keeps
+// behind by a forward navigation that threw is invisible on screen until
-// that race out of the assertion; a stack that never becomes the expected
+// the user presses Back one time too many — which is exactly the
-// one fails with what it actually was.
+// second-order damage #150 did — so the stack itself is what gets asserted.
-const VIEW_STACK_SETTLE_MS = 5000;
+async function persistedViewStack(page) {
+    return (await persistedField(page, "viewStack")) || [];
+}
 
-async function waitForViewStack(page, expected, where) {
+// Nothing here can await the popup's saves. showView() fires saveState()
+// without awaiting it, and a Settings control's "change" handler awaits its
+// save only after click() or selectOption() has already returned. So the
+// write lands shortly after the screen or the control changes, and a popup
+// closed before then loses it. Polling for the expected value keeps that
+// race out of the assertion and out of the close; a value that never
+// arrives fails with what it actually was.
+const SAVE_SETTLE_MS = 5000;
+
+async function waitForPersisted(page, field, expected, where) {
     const want = JSON.stringify(expected);
-    const deadline = Date.now() + VIEW_STACK_SETTLE_MS;
+    const deadline = Date.now() + SAVE_SETTLE_MS;
     let seen;
     for (;;) {
-        seen = await persistedViewStack(page);
+        seen = await persistedField(page, field);
         if (JSON.stringify(seen) === want) return;
         if (Date.now() >= deadline) break;
         await sleep(50);
     }
     throw new Error(
-        "navigation stack " +
+        "the persisted " +
+            field +
+            " " +
             where +
             " is " +
             JSON.stringify(seen) +
@@ -257,12 +268,18 @@ test("Back from Add Token unwinds the stack exactly once (#150)", async (env) =>
 
     await env.page.locator("#wallet-list .btn-addr-info").first().click();
     await visible(env.page, "#view-address");
-    await waitForViewStack(env.page, base.concat("main"), "on address detail");
+    await waitForPersisted(
+        env.page,
+        "viewStack",
+        base.concat("main"),
+        "on address detail",
+    );
 
     await env.page.click("#btn-add-token");
     await visible(env.page, "#view-add-token");
-    await waitForViewStack(
+    await waitForPersisted(
         env.page,
+        "viewStack",
         base.concat("main", "address"),
         "on the add token screen",
     );
@@ -273,15 +290,16 @@ test("Back from Add Token unwinds the stack exactly once (#150)", async (env) =>
         !(await env.page.isVisible("#view-add-token")),
         "the add token screen is still showing after Back",
     );
-    await waitForViewStack(
+    await waitForPersisted(
         env.page,
+        "viewStack",
         base.concat("main"),
         "after Back from add token",
     );
 
     await env.page.click("#btn-address-back");
     await visible(env.page, "#view-main");
-    await waitForViewStack(env.page, base, "after a second Back");
+    await waitForPersisted(env.page, "viewStack", base, "after a second Back");
 });
 
 test("a common-token quick-pick fills in the contract address (#150)", async (env) => {
@@ -679,6 +697,12 @@ test("reopening the popup never lands on the phrase screen (#161)", async (env)
     await openPhraseScreen(env.page);
     await revealPhrase(env.page);
 
+    await waitForPersisted(
+        env.page,
+        "currentView",
+        "show-phrase",
+        "before closing the popup",
+    );
     await env.page.close();
     env.page = await openPopup(env.ctx, env.popupUrl);
     await visible(env.page, "#view-main");
@@ -714,10 +738,20 @@ function addressScreenState(page) {
 
 // Close and reopen the page rather than reload it: that is what the toolbar
 // popup does, and it is the only thing that produces the unrendered views.
-async function reopenPopup(env, restoredView) {
+// The popup reopens on the view it last saved, so the close waits until
+// `view` is the one saved. That wait cannot see a save that leaves the value
+// as it was: a caller whose popup already had `view` saved waits for a
+// screen in between first.
+async function reopenPopup(env, view) {
+    await waitForPersisted(
+        env.page,
+        "currentView",
+        view,
+        "before closing the popup",
+    );
     await env.page.close();
     env.page = await openPopup(env.ctx, env.popupUrl);
-    await visible(env.page, restoredView);
+    await visible(env.page, "#view-" + view);
 }
 
 // The reproduction from the issue, step for step.
@@ -732,7 +766,7 @@ test("Back after reopening the popup renders the address screen (#268)", async (
     await env.page.click("#btn-settings");
     await visible(env.page, "#view-settings");
 
-    await reopenPopup(env, "#view-settings");
+    await reopenPopup(env, "settings");
 
     await env.page.click("#btn-settings-back");
     await visible(env.page, "#view-address");
@@ -789,10 +823,18 @@ test("Back after reopening the popup renders the Receive screen (#268)", async (
             JSON.stringify(before.address),
     );
 
+    // The test above left `settings` saved too, so reopenPopup() could not
+    // tell this page's save of it from that one without a save in between.
+    await waitForPersisted(
+        env.page,
+        "currentView",
+        "receive",
+        "on the Receive screen",
+    );
     await env.page.click("#btn-settings");
     await visible(env.page, "#view-settings");
 
-    await reopenPopup(env, "#view-settings");
+    await reopenPopup(env, "settings");
 
     await env.page.click("#btn-settings-back");
     await visible(env.page, "#view-receive");
@@ -1175,11 +1217,24 @@ const NONDEFAULT_NETWORK = "sepolia";
 test("the theme and network selectors carry a non-default persisted value (#229)", async (env) => {
     await openSettings(env.page);
 
-    // selectOption() fires "change", which is what the handlers bind.
+    // selectOption() fires "change", which is what the handlers bind. It
+    // returns before the handler's save lands, hence each wait.
     await env.page.selectOption("#settings-theme", NONDEFAULT_THEME);
+    await waitForPersisted(
+        env.page,
+        "theme",
+        NONDEFAULT_THEME,
+        "after the switch",
+    );
     await env.page.selectOption("#settings-network", NONDEFAULT_NETWORK);
+    await waitForPersisted(
+        env.page,
+        "networkId",
+        NONDEFAULT_NETWORK,
+        "after the switch",
+    );
 
-    await reopenPopup(env, "#view-settings");
+    await reopenPopup(env, "settings");
 
     assertSelectors(
         await selectorValues(env.page),
@@ -1198,9 +1253,16 @@ test("the theme and network selectors carry a non-default persisted value (#229)
     // fixture never customised and so are the mainnet defaults
     // src/shared/state.js starts with.
     await env.page.selectOption("#settings-theme", "system");
+    await waitForPersisted(env.page, "theme", "system", "after the restore");
     await env.page.selectOption("#settings-network", "mainnet");
+    await waitForPersisted(
+        env.page,
+        "networkId",
+        "mainnet",
+        "after the restore",
+    );
 
-    await reopenPopup(env, "#view-settings");
+    await reopenPopup(env, "settings");
 
     assertSelectors(
         await selectorValues(env.page),
@@ -1225,8 +1287,14 @@ test("a spam filter toggled in Settings survives a popup reopen (#229)", async (
         immediately.checked === false,
         "clicking #" + TOGGLED_FILTER + " did not clear it",
     );
+    await waitForPersisted(
+        env.page,
+        "hideDustTransactions",
+        false,
+        "after clearing #" + TOGGLED_FILTER,
+    );
 
-    await reopenPopup(env, "#view-settings");
+    await reopenPopup(env, "settings");
 
     const after = await checkboxStates(env.page);
     for (const { id } of SPAM_FILTER_CHECKBOXES) {
@@ -1243,8 +1311,14 @@ test("a spam filter toggled in Settings survives a popup reopen (#229)", async (
 test("turning the same filter back on survives a reopen too (#229)", async (env) => {
     await openSettings(env.page);
     await env.page.click("#" + TOGGLED_FILTER);
+    await waitForPersisted(
+        env.page,
+        "hideDustTransactions",
+        true,
+        "after setting #" + TOGGLED_FILTER + " again",
+    );
 
-    await reopenPopup(env, "#view-settings");
+    await reopenPopup(env, "settings");
 
     // Restores the fixture the later sections inherit, and rules out a
     // checkbox that persists "off" only because it is stuck there.
@@ -2365,7 +2439,7 @@ test("a token whose symbol() returns markup renders as text (#307)", async (env)
 
     // Close and reopen so the refresh that runs on open fetches balances
     // with the hostile symbol in them.
-    await reopenPopup(env, "#view-address");
+    await reopenPopup(env, "address");
     await env.page.waitForFunction(
         (addr) =>
             !!document.querySelector(
@@ -2431,7 +2505,7 @@ test("a token whose symbol() returns markup renders as text (#307)", async (env)
     // Put the fixture back before the next test reads it, and let the
     // stored balances be rewritten with the honest symbol.
     env.routeOpts.tokenSymbolOverride = null;
-    await reopenPopup(env, "#view-main");
+    await reopenPopup(env, "main");
     await env.page.waitForFunction(
         (addr) => {
             const row = document.querySelector(
@@ -2738,7 +2812,7 @@ async function closeApprovalPages(ctx) {
 //   #btn-reject on the site prompt — NOT self-proving. A page that went away
 //     without the click landing disconnects the approval port, the background
 //     settles that as 4001, and 4001 is exactly what assertUserRejection
-//     accepts. That call site arms the click trace below and asserts it.
+//     accepts. Both call sites arm the click trace below and assert it.
 //
 // A button that is missing or unclickable raises a different error, which is
 // rethrown.
@@ -3124,7 +3198,9 @@ test("a connect request from a blocklisted site is flagged (#219)", async (env)
             // Not remembered: a remembered decision for this origin would
             // outlive the test.
             await popup.uncheck("#approve-remember");
-            await popup.click("#btn-reject");
+            await armClickTrace(env, popup, "#btn-reject");
+            await clickAndClose(popup, "#btn-reject");
+            await assertClickLanded(env, "#btn-reject");
 
             await assertUserRejection(
                 phishingDapp,
@@ -3232,6 +3308,64 @@ test("personal_sign rejected returns a rejection to the page (#183)", async (env
     );
 });
 
+// A right-to-left character must not move the characters around it: U+05C3
+// between "5" and "00" would otherwise put "500" on screen before it. A
+// paragraph separator (U+2029) before it, left in the text, would end the
+// byte-order layout and bring that back
+// (https://git.eeqj.de/sneak/AutistMask/issues/403).
+test("a personal message is laid out in the order of its bytes (#403)", async (env) => {
+    const rightToLeft = String.fromCodePoint(0x05c3);
+    const text =
+        "Sign in" +
+        String.fromCodePoint(0x2029) +
+        "Pay 5" +
+        rightToLeft +
+        "00 ETH";
+    await startRequest(env.dapp, "sign-bidi", "personal_sign", [
+        hexlify(toUtf8Bytes(text)),
+        env.expectedAddress,
+    ]);
+    const popup = await waitForApprovalWindow(env.ctx);
+    await visible(popup, "#view-approve-sign");
+
+    // The text on screen, marks included, and the left edge of each of its
+    // characters, in byte order. A character the browser's fonts draw with
+    // no width shares its neighbour's edge.
+    const shown = await popup.evaluate(() => {
+        const message = document.getElementById("approve-sign-message");
+        const walker = document.createTreeWalker(message, NodeFilter.SHOW_TEXT);
+        const range = document.createRange();
+        let text = "";
+        const lefts = [];
+        for (let node = walker.nextNode(); node; node = walker.nextNode()) {
+            for (let i = 0; i < node.length; i++) {
+                range.setStart(node, i);
+                range.setEnd(node, i + 1);
+                lefts.push(range.getBoundingClientRect().left);
+            }
+            text += node.data;
+        }
+        return { text, lefts };
+    });
+    await clickAndClose(popup, "#btn-reject-sign");
+    await assertUserRejection(
+        env.dapp,
+        "sign-bidi",
+        "the byte-order personal_sign rejection",
+    );
+
+    assert(
+        shown.text === "Sign inU+2029Pay 5" + rightToLeft + "00 ETH",
+        "the paragraph separator is not shown as a mark: " +
+            JSON.stringify(shown.text),
+    );
+    assert(
+        shown.lefts.every((left, i) => i === 0 || left >= shown.lefts[i - 1]),
+        "the personal message is not laid out in byte order: " +
+            JSON.stringify(shown.lefts),
+    );
+});
+
 test("eth_signTypedData_v4 signs, and the signature recovers (#183)", async (env) => {
     await startRequest(env.dapp, "typed", "eth_signTypedData_v4", [
         env.expectedAddress,

tests/holders.test.js

@@ -57,6 +57,39 @@ describe("parseHoldersCount", () => {
         expect(parseHoldersCount("many")).toBeNull();
         expect(parseHoldersCount(NaN)).toBeNull();
     });
+
+    // Each of these starts with a digit, so reading only the leading digits
+    // would turn it into a small reported count, and a small count is
+    // exactly what hides a token as spam (issue #251).
+    test.each(["1,000", "0x10", "1e3", "12 holders"])(
+        "%p is not read in part: it is unknown",
+        (raw) => {
+            expect(parseHoldersCount(raw)).toBeNull();
+        },
+    );
+
+    test("a negative count is unknown", () => {
+        expect(parseHoldersCount("-5")).toBeNull();
+        expect(parseHoldersCount(-5)).toBeNull();
+    });
+
+    // A number holds a whole number exactly only up to 2^53 - 1.  Past that a
+    // string of digits would come back rounded, and a long enough one as
+    // Infinity, which would pass every holder-count floor.
+    test("a count too large for a number to hold exactly is unknown", () => {
+        expect(parseHoldersCount("9007199254740993")).toBeNull();
+        expect(parseHoldersCount("9".repeat(400))).toBeNull();
+        expect(parseHoldersCount(2 ** 53)).toBeNull();
+    });
+
+    test("the largest count a number holds exactly still parses", () => {
+        expect(parseHoldersCount("9007199254740991")).toBe(
+            Number.MAX_SAFE_INTEGER,
+        );
+        expect(parseHoldersCount(Number.MAX_SAFE_INTEGER)).toBe(
+            Number.MAX_SAFE_INTEGER,
+        );
+    });
 });
 
 describe("isLowHolderCount", () => {

tests/nativeCurrency.test.js

@@ -0,0 +1,461 @@
+// The native token's label on the screens that show a native amount.
+//
+// src/shared/networks.js gives each network a nativeCurrency, `ETH` on mainnet
+// and `SepoliaETH` on Sepolia, and nothing read it: every screen wrote a
+// hardcoded "ETH", so on Sepolia the balance, the value and the fee all read
+// ETH (https://git.eeqj.de/sneak/AutistMask/issues/372). Each line is asserted
+// on both networks, through the real Send, confirmation and approval screens,
+// with only the node and the DOM stubbed. So is that a token cannot pass for
+// the native token by reporting its label, and that a transaction's figures
+// carry its own network's label when another network is active.
+
+"use strict";
+
+jest.mock("ethers", () => {
+    const actual = jest.requireActual("ethers");
+    class StubProvider {
+        async lookupAddress() {
+            return null;
+        }
+        // 10 gwei expected, 20 gwei reserved per gas.
+        async getFeeData() {
+            return { maxFeePerGas: 20000000000n, gasPrice: 10000000000n };
+        }
+        async estimateGas() {
+            return 21000n;
+        }
+        async getCode() {
+            return "0x";
+        }
+        async getTransactionCount() {
+            return 1;
+        }
+        async getTransactionReceipt() {
+            return { blockNumber: 21000000 };
+        }
+    }
+    return {
+        ...actual,
+        JsonRpcProvider: StubProvider,
+        Network: { from: () => ({}) },
+    };
+});
+
+jest.mock("../src/shared/log", () => ({
+    log: {
+        debugf: () => {},
+        infof: () => {},
+        warnf: () => {},
+        errorf: () => {},
+    },
+    debugFetch: jest.fn(async () => ({
+        ok: true,
+        status: 200,
+        json: async () => ({ items: [] }),
+    })),
+    urlOrigin: () => "",
+    setRuntimeDebug: () => {},
+    isDebug: () => false,
+}));
+
+// Signing a send succeeds without a key, and sending answers with a hash.
+jest.mock("../src/shared/vault", () => ({
+    ...jest.requireActual("../src/shared/vault"),
+    decryptWithPassword: async () => "secret",
+}));
+jest.mock("../src/shared/wallet", () => ({
+    ...jest.requireActual("../src/shared/wallet"),
+    getSignerForAddress: () => ({
+        connect: () => ({
+            populateTransaction: async (request) => request,
+            sendTransaction: async () => ({ hash: "0x" + "3".repeat(64) }),
+        }),
+    }),
+}));
+
+global.fetch = jest.fn(() => {
+    throw new Error("tests must not perform network requests");
+});
+
+// The approval the background hands the approval screen. Set per test.
+let approvalDetails = null;
+
+const { makeStorageStub } = require("./support/storageStub");
+global.chrome = {
+    storage: makeStorageStub(),
+    runtime: {
+        connect: () => ({
+            postMessage() {},
+            disconnect() {},
+            onDisconnect: { addListener() {} },
+        }),
+        sendMessage(message, callback) {
+            callback(
+                message.type === "AUTISTMASK_GET_APPROVAL"
+                    ? approvalDetails
+                    : undefined,
+            );
+        },
+    },
+};
+
+// A stub DOM: every id resolves to a recording element.
+const elements = new Map();
+
+function makeEl(id) {
+    const handlers = new Map();
+    return {
+        id,
+        textContent: "",
+        innerHTML: "",
+        value: "",
+        disabled: false,
+        style: {},
+        dataset: {},
+        classList: {
+            add() {},
+            remove() {},
+            toggle() {},
+            contains: () => false,
+        },
+        handlers,
+        children: [],
+        addEventListener(name, fn) {
+            handlers.set(name, fn);
+        },
+        appendChild(child) {
+            this.children.push(child);
+            return child;
+        },
+        querySelectorAll: () => [],
+        querySelector: () => null,
+        remove() {},
+        focus() {},
+        // Views reach for .parentElement to hide whole sections.
+        get parentElement() {
+            return global.document.getElementById(id + "-parent");
+        },
+    };
+}
+
+global.document = {
+    getElementById(id) {
+        if (!elements.has(id)) elements.set(id, makeEl(id));
+        return elements.get(id);
+    },
+    createElement: (tag) => makeEl(tag),
+    body: { prepend() {}, appendChild() {} },
+    addEventListener() {},
+};
+global.navigator = { clipboard: { writeText() {} } };
+
+const { state } = require("../src/shared/state");
+const { NETWORKS } = require("../src/shared/networks");
+const { clearPrices } = require("../src/shared/prices");
+const send = require("../src/popup/views/send");
+const confirmTx = require("../src/popup/views/confirmTx");
+const approval = require("../src/popup/views/approval");
+const transactionDetail = require("../src/popup/views/transactionDetail");
+const txStatus = require("../src/popup/views/txStatus");
+const { balanceLinesForAddress } = require("../src/popup/views/helpers");
+const { filterTransactions } = require("../src/shared/transactions");
+const { debugFetch } = require("../src/shared/log");
+
+const HOLDER = "0x" + "a".repeat(40);
+const RECIPIENT = "0xC0FfEE0000000000000000000000000000c0fFEe";
+// A token contract that is not in the bundled token list.
+const TOKEN_CONTRACT = "0xd05339f9ea5ab9d9f03b9d57f671d2abd1f55c82";
+
+function text(id) {
+    return global.document.getElementById(id).textContent;
+}
+
+// Press Review on the Send screen for a native send of `amount`, and show the
+// confirmation screen it leads to with its fee estimate settled.
+async function confirmSend(amount) {
+    let txInfo = null;
+    send.init({ showConfirmTx: (info) => (txInfo = info) });
+    state.selectedToken = "ETH";
+    global.document.getElementById("send-to").value = RECIPIENT;
+    global.document.getElementById("send-amount").value = amount;
+    await global.document
+        .getElementById("btn-send-review")
+        .handlers.get("click")();
+    confirmTx.show(txInfo);
+    for (let i = 0; i < 10; i++) await new Promise((r) => setTimeout(r, 0));
+}
+
+// The approval screen for a dApp transaction sending 0.01 of the native token
+// with 21000 gas at up to 20 gwei, on the network with `chainId`.
+async function approveTx(chainId) {
+    approvalDetails = {
+        type: "tx",
+        origin: "https://dapp.example",
+        approvedFrom: HOLDER,
+        approvedTx: {
+            to: RECIPIENT,
+            value: "10000000000000000",
+            data: "0x",
+            chainId,
+            gasLimit: "21000",
+            maxFeePerGas: "20000000000",
+            nonce: 0,
+        },
+    };
+    await approval.show("1");
+}
+
+describe.each([
+    ["mainnet", "ETH"],
+    ["sepolia", "SepoliaETH"],
+])("on %s the native token reads %s", (networkId, symbol) => {
+    beforeEach(() => {
+        elements.clear();
+        clearPrices();
+        state.networkId = networkId;
+        state.wallets = [
+            {
+                name: "Wallet 1",
+                addresses: [{ address: HOLDER, balance: "1.5" }],
+            },
+        ];
+        state.selectedWallet = 0;
+        state.selectedAddress = 0;
+        state.trackedTokens = [];
+        state.fraudContracts = [];
+        state.currentView = null;
+    });
+
+    test("the balance", async () => {
+        const addr = state.wallets[0].addresses[0];
+        expect(balanceLinesForAddress(addr, [], false)).toContain(
+            `<span>${symbol}</span><span>1.5000</span>`,
+        );
+        state.selectedToken = "ETH";
+        send.updateSendBalance();
+        expect(text("send-balance")).toBe("Current balance: 1.5000 " + symbol);
+        await confirmSend("0.1");
+        expect(text("confirm-balance")).toBe("1.5000 " + symbol);
+    });
+
+    test("the value", async () => {
+        await confirmSend("0.1");
+        expect(text("confirm-type")).toBe("Native " + symbol + " transfer");
+        expect(text("confirm-amount")).toBe("0.1 " + symbol);
+        await approveTx(NETWORKS[networkId].chainId);
+        expect(text("approve-tx-value")).toBe("0.0100 " + symbol);
+    });
+
+    test("the fee", async () => {
+        await confirmSend("0.1");
+        // 21000 gas at 10 gwei expected, at 20 gwei reserved.
+        expect(text("confirm-fee-amount")).toBe("~0.0002 " + symbol);
+        expect(text("confirm-fee-reserve")).toBe(
+            "up to 0.0004 " + symbol + " reserved",
+        );
+        expect(text("confirm-gas-error")).toContain(
+            "You do not have enough " + symbol + " to pay the network fee",
+        );
+        await approveTx(NETWORKS[networkId].chainId);
+        expect(text("approve-tx-fee")).toBe("0.0004 " + symbol);
+    });
+
+    test("the contract-recipient warning", async () => {
+        await confirmSend("0.1");
+        expect(text("confirm-contract-warning")).toContain(
+            "Sending " + symbol + " or tokens directly to a contract",
+        );
+    });
+
+    // A token reports whatever symbol it likes. One reporting the label the
+    // wallet shows its native token under, on this network or any other, is
+    // a fake, exactly as one reporting `ETH` always was.
+    test.each(["ETH", symbol])(
+        "a token claiming %s is dropped from the history and the Send selector",
+        (claim) => {
+            const result = filterTransactions(
+                [
+                    {
+                        hash: "0x" + "1".repeat(64),
+                        symbol: claim,
+                        contractAddress: TOKEN_CONTRACT,
+                        holders: 900000,
+                        valueGwei: null,
+                        isContractCall: false,
+                    },
+                ],
+                { hideSpoofedSymbols: true },
+            );
+            expect(result.transactions).toEqual([]);
+            expect(result.newFraudContracts).toEqual([TOKEN_CONTRACT]);
+
+            send.renderSendTokenSelect({
+                address: HOLDER,
+                tokenBalances: [
+                    {
+                        address: TOKEN_CONTRACT,
+                        symbol: claim,
+                        decimals: 18,
+                        balance: "5",
+                        holders: 900000,
+                    },
+                ],
+            });
+            expect(
+                global.document.getElementById("send-token").children,
+            ).toEqual([]);
+        },
+    );
+
+    // The detail screen tells the two apart by the token contract, which only
+    // a token transfer has, so a token reporting the native label still reads
+    // as a token transfer.
+    test("the transaction detail screen's type line", () => {
+        const entry = {
+            hash: "0x" + "2".repeat(64),
+            from: RECIPIENT,
+            to: HOLDER,
+            value: "1.0000",
+            exactValue: "1.0",
+            symbol,
+            timestamp: 1790000000,
+            isError: false,
+            direction: "received",
+            directionLabel: "Received",
+            chainId: NETWORKS[networkId].chainId,
+        };
+        transactionDetail.show({ ...entry, contractAddress: null });
+        expect(text("tx-detail-type")).toBe("Native " + symbol + " Transfer");
+        transactionDetail.show({ ...entry, contractAddress: TOKEN_CONTRACT });
+        expect(text("tx-detail-type")).toBe("ERC-20 Token Transfer");
+    });
+
+    test("the insufficient-balance error", async () => {
+        await confirmSend("2");
+        expect(
+            global.document.getElementById("confirm-errors").innerHTML,
+        ).toContain(
+            "You have 1.5000 " +
+                symbol +
+                " but are trying to send 2 " +
+                symbol +
+                ".",
+        );
+    });
+});
+
+// A transaction's value and fee are in the native currency of the network the
+// transaction is on, which need not be the active one. A site can switch the
+// active network after its transaction is prepared and back before it is
+// signed, and a popup opened after a switch shows a sent or listed transaction
+// again. The wallet's balances follow the active network; these do not.
+describe.each([
+    ["mainnet", "sepolia", "ETH"],
+    ["sepolia", "mainnet", "SepoliaETH"],
+])(
+    "a %s transaction shown with %s active reads %s",
+    (txNetworkId, activeNetworkId, symbol) => {
+        const chainId = NETWORKS[txNetworkId].chainId;
+        const hash = "0x" + "3".repeat(64);
+
+        beforeEach(() => {
+            elements.clear();
+            clearPrices();
+            state.networkId = activeNetworkId;
+            state.wallets = [
+                {
+                    name: "Wallet 1",
+                    addresses: [{ address: HOLDER, balance: "1.5" }],
+                },
+            ];
+            state.selectedWallet = 0;
+            state.selectedAddress = 0;
+            state.trackedTokens = [];
+            state.fraudContracts = [];
+            state.currentView = null;
+            txStatus.init({ doRefreshAndRender() {} });
+        });
+
+        afterEach(() => {
+            txStatus.endWait();
+        });
+
+        test("the approval screen's value and fee", async () => {
+            await approveTx(chainId);
+            expect(text("approve-tx-network")).toBe(NETWORKS[txNetworkId].name);
+            expect(text("approve-tx-value")).toBe("0.0100 " + symbol);
+            expect(text("approve-tx-fee")).toBe("0.0004 " + symbol);
+        });
+
+        test("the wait, success and error screens", async () => {
+            const txInfo = {
+                from: HOLDER,
+                to: RECIPIENT,
+                amount: "0.0100",
+                token: "ETH",
+                tokenSymbol: null,
+                chainId,
+            };
+            txStatus.showWait(txInfo, hash);
+            expect(text("wait-tx-summary")).toBe("0.0100 " + symbol);
+            txStatus.showError(txInfo, hash, "Failed.");
+            expect(text("error-tx-summary")).toBe("0.0100 " + symbol);
+            // A later popup resumes the wait, and the receipt is there.
+            state.viewData = {
+                pendingWait: { txInfo, hash, broadcastTime: Date.now() },
+            };
+            txStatus.restoreWait();
+            for (let i = 0; i < 10; i++) {
+                await new Promise((r) => setTimeout(r, 0));
+            }
+            expect(text("success-tx-summary")).toBe("0.0100 " + symbol);
+        });
+
+        // Sent from the Send screen on the transaction's network, then
+        // resumed by a popup that opens after the active network changed.
+        test("the wait screen after a send", async () => {
+            state.networkId = txNetworkId;
+            await confirmSend("0.1");
+            confirmTx.init({});
+            global.document.getElementById("confirm-tx-password").value = "pw";
+            await global.document
+                .getElementById("btn-confirm-send")
+                .handlers.get("click")();
+            expect(text("wait-tx-summary")).toBe("0.1 " + symbol);
+            state.networkId = activeNetworkId;
+            txStatus.restoreWait();
+            expect(text("wait-tx-summary")).toBe("0.1 " + symbol);
+        });
+
+        test("the transaction detail screen's type line and fee", async () => {
+            debugFetch.mockImplementationOnce(async () => ({
+                ok: true,
+                status: 200,
+                json: async () => ({ fee: { value: "21000000000000" } }),
+            }));
+            transactionDetail.show({
+                hash,
+                from: RECIPIENT,
+                to: HOLDER,
+                value: "1.0000",
+                exactValue: "1.0",
+                symbol,
+                timestamp: 1790000000,
+                isError: false,
+                direction: "received",
+                directionLabel: "Received",
+                contractAddress: null,
+                chainId,
+            });
+            expect(text("tx-detail-type")).toBe(
+                "Native " + symbol + " Transfer",
+            );
+            for (let i = 0; i < 10; i++) {
+                await new Promise((r) => setTimeout(r, 0));
+            }
+            expect(
+                global.document.getElementById("tx-detail-fee").innerHTML,
+            ).toContain("0.000021 " + symbol);
+        });
+    },
+);

tests/persistedFieldContract.test.js

@@ -722,6 +722,28 @@ describe("the base profile the sweep corrupts", () => {
     }
 });
 
+// Home, AddressDetail and AddressToken load their transactions inside a catch
+// that only logs, so a boot that fails there still renders the view and passes
+// the tests above while none of that code runs.
+describe("the base profile loads transactions", () => {
+    for (const view of ["main", "address", "address-token"]) {
+        test(`on ${view} without logging a failure`, async () => {
+            const consoleError = jest.spyOn(console, "error");
+            try {
+                await bootPopup(restoringOnto(view));
+                const failures = consoleError.mock.calls
+                    .map((args) => args.join(" "))
+                    .filter((line) =>
+                        /loadHomeTxs failed|loadTransactions failed/.test(line),
+                    );
+                expect(failures).toEqual([]);
+            } finally {
+                consoleError.mockRestore();
+            }
+        });
+    }
+});
+
 // A field the ROUTER itself reads — the two it gates on and the two
 // hasValidAddress() indexes with. A hostile value in one of these legitimately
 // changes which view renders, so each gets its own boot per view and is held

tests/personalSignDisplay.test.js

@@ -0,0 +1,229 @@
+// The signature prompt shows a personal message as the bytes that are signed
+// (https://git.eeqj.de/sneak/AutistMask/issues/403): the raw data in hex, the
+// text it decodes to with control characters, line and paragraph separators
+// and characters that paint nothing marked rather than obeyed, markup shown as
+// text, laid out in byte order, and a message that is not hex as plain text
+// that cannot be signed.
+//
+// Driven against a minimal DOM stub in the shape
+// tests/approvalOrigin.test.js uses. That the layout keeps right-to-left
+// characters in byte order needs a real browser: tests/e2e/run.js checks it.
+
+globalThis.chrome = {
+    storage: { local: { get: async () => ({}), set: async () => {} } },
+};
+
+const { hexlify, toUtf8Bytes } = require("ethers");
+const { state } = require("../src/shared/state");
+const approval = require("../src/popup/views/approval");
+
+const FROM = "0x0000000000000000000000000000000000000a11";
+
+// Built from their code points so that this file holds none of them.
+const RIGHT_TO_LEFT_OVERRIDE = String.fromCodePoint(0x202e);
+const POP_DIRECTIONAL_FORMATTING = String.fromCodePoint(0x202c);
+const ZERO_WIDTH_SPACE = String.fromCodePoint(0x200b);
+const VARIATION_SELECTOR_1 = String.fromCodePoint(0xfe00);
+const VARIATION_SELECTOR_17 = String.fromCodePoint(0xe0100);
+const HANGUL_FILLER = String.fromCodePoint(0x3164);
+const LINE_SEPARATOR = String.fromCodePoint(0x2028);
+const PARAGRAPH_SEPARATOR = String.fromCodePoint(0x2029);
+
+function makeElement(id) {
+    const classes = new Set();
+    return {
+        id,
+        textContent: "",
+        value: "",
+        innerHTML: "",
+        disabled: false,
+        style: {},
+        dataset: {},
+        classList: {
+            add: (...names) => names.forEach((n) => classes.add(n)),
+            remove: (...names) => names.forEach((n) => classes.delete(n)),
+            contains: (n) => classes.has(n),
+            toggle: (n, force) => {
+                const on = force === undefined ? !classes.has(n) : force;
+                if (on) classes.add(n);
+                else classes.delete(n);
+                return on;
+            },
+        },
+        addEventListener: () => {},
+        querySelectorAll: () => [],
+        appendChild: () => {},
+    };
+}
+
+function makeDocument() {
+    const els = new Map();
+    return {
+        getElementById(id) {
+            if (id === "debug-banner") return null;
+            if (!els.has(id)) els.set(id, makeElement(id));
+            return els.get(id);
+        },
+        createElement: () => makeElement("created"),
+        body: { prepend: () => {} },
+    };
+}
+
+function node(id) {
+    return globalThis.document.getElementById(id);
+}
+
+// Open the signature prompt for a personal_sign of `message`, the way the
+// popup does: it asks the background for the approval and show() draws it.
+async function openPersonalSign(message) {
+    globalThis.document = makeDocument();
+    globalThis.window = { location: { search: "" } };
+    globalThis.chrome.runtime = {
+        connect: () => ({ postMessage: () => {} }),
+        sendMessage: (msg, reply) => {
+            if (!reply) return;
+            if (msg.type !== "AUTISTMASK_GET_APPROVAL") return reply(null);
+            reply({
+                type: "sign",
+                origin: "https://dapp.example",
+                isPhishingDomain: false,
+                approvedFrom: FROM,
+                signParams: { method: "personal_sign", message, from: FROM },
+            });
+        },
+    };
+    approval.init({});
+    await approval.show(1);
+}
+
+// The message box's markup as the text a reader sees: tags dropped.
+function shownMessage() {
+    return node("approve-sign-message").innerHTML.replace(/<[^>]*>/g, "");
+}
+
+beforeEach(() => {
+    state.wallets = [];
+    state.activeAddress = FROM;
+    state.viewData = {};
+    state.viewStack = [];
+    state.currentView = null;
+});
+
+test("a right-to-left override is marked, so the text reads in byte order", async () => {
+    // Obeyed, the override shows "0001" as "1000".
+    const text =
+        "Pay " +
+        RIGHT_TO_LEFT_OVERRIDE +
+        "0001" +
+        POP_DIRECTIONAL_FORMATTING +
+        " ETH";
+    await openPersonalSign(hexlify(toUtf8Bytes(text)));
+    const html = node("approve-sign-message").innerHTML;
+    expect(html).not.toContain(RIGHT_TO_LEFT_OVERRIDE);
+    expect(html).not.toContain(POP_DIRECTIONAL_FORMATTING);
+    expect(shownMessage()).toBe("Pay U+202E0001U+202C ETH");
+});
+
+test("a zero-width character is marked", async () => {
+    await openPersonalSign(
+        hexlify(toUtf8Bytes("pay" + ZERO_WIDTH_SPACE + "pal.com")),
+    );
+    expect(node("approve-sign-message").innerHTML).not.toContain(
+        ZERO_WIDTH_SPACE,
+    );
+    expect(shownMessage()).toBe("payU+200Bpal.com");
+});
+
+test("variation selectors and a Hangul filler are marked", async () => {
+    // Each paints nothing, so a page could hide bytes after "Sign in".
+    await openPersonalSign(
+        hexlify(
+            toUtf8Bytes(
+                "Sign in" +
+                    VARIATION_SELECTOR_1 +
+                    VARIATION_SELECTOR_17 +
+                    HANGUL_FILLER,
+            ),
+        ),
+    );
+    expect(shownMessage()).toBe("Sign inU+FE00U+E0100U+3164");
+});
+
+test("the message is laid out in byte order", async () => {
+    await openPersonalSign(hexlify(toUtf8Bytes("Hello")));
+    expect(
+        node("approve-sign-message").classList.contains("am-byte-order"),
+    ).toBe(true);
+});
+
+test("a control character other than a line feed is marked", async () => {
+    await openPersonalSign(hexlify(toUtf8Bytes("a\u0000b\tc")));
+    expect(shownMessage()).toBe("aU+0000bU+0009c");
+});
+
+test("line and paragraph separators are marked", async () => {
+    // Left in the text, a paragraph separator would end the byte-order
+    // layout for everything after it.
+    await openPersonalSign(
+        hexlify(toUtf8Bytes("a" + LINE_SEPARATOR + "b" + PARAGRAPH_SEPARATOR)),
+    );
+    const html = node("approve-sign-message").innerHTML;
+    expect(html).not.toContain(LINE_SEPARATOR);
+    expect(html).not.toContain(PARAGRAPH_SEPARATOR);
+    expect(shownMessage()).toBe("aU+2028bU+2029");
+});
+
+test("a line feed is shown as a line break", async () => {
+    await openPersonalSign(hexlify(toUtf8Bytes("Sign in\nNonce: 7")));
+    expect(node("approve-sign-message").innerHTML).toBe("Sign in<br>Nonce: 7");
+});
+
+// The message box is written as HTML, so a site's markup has to arrive there
+// escaped, as the text it is.
+const MARKUP = "<b>x</b><img src=x onerror=alert(1)>";
+
+test.each([
+    ["a hex message", hexlify(toUtf8Bytes(MARKUP))],
+    ["a message that is not hex", MARKUP],
+])("markup in %s is shown as text, not as markup", async (_, message) => {
+    await openPersonalSign(message);
+    expect(node("approve-sign-message").innerHTML).toBe(
+        "&lt;b&gt;x&lt;/b&gt;&lt;img src=x onerror=alert(1)&gt;",
+    );
+});
+
+test("the raw hex is shown alongside the text", async () => {
+    await openPersonalSign("0x48656c6c6f");
+    expect(shownMessage()).toBe("Hello");
+    expect(node("approve-sign-hex").textContent).toBe("0x48656c6c6f");
+    expect(node("approve-sign-hex-section").classList.contains("hidden")).toBe(
+        false,
+    );
+});
+
+test("hex with an uppercase 0X is read as hex, as signing reads it", async () => {
+    await openPersonalSign("0X48656C6C6F");
+    expect(shownMessage()).toBe("Hello");
+    expect(node("approve-sign-hex").textContent).toBe("0X48656C6C6F");
+    expect(node("btn-approve-sign").disabled).toBe(false);
+});
+
+test("bytes that are not text are shown only as hex", async () => {
+    await openPersonalSign("0xff00");
+    expect(node("approve-sign-message").textContent).toBe(
+        "This message is not text.",
+    );
+    expect(node("approve-sign-hex").textContent).toBe("0xff00");
+});
+
+test("a message that is not hex is shown as text and cannot be signed", async () => {
+    await openPersonalSign("Hello world");
+    expect(shownMessage()).toBe("Hello world");
+    expect(node("approve-sign-error").textContent).toBe(
+        "This message is plain text, not hex, so it cannot be signed.",
+    );
+    expect(node("btn-approve-sign").disabled).toBe(true);
+    expect(node("approve-sign-hex-section").classList.contains("hidden")).toBe(
+        true,
+    );
+});

tests/rpcErrorLog.test.js

@@ -12,7 +12,11 @@
 // every log level is printed.
 
 const { FetchRequest } = require("ethers");
-const { getProvider, refreshBalances } = require("../src/shared/balances");
+const {
+    getProvider,
+    lookupTokenInfo,
+    refreshBalances,
+} = require("../src/shared/balances");
 const { getFullWarnings } = require("../src/shared/addressWarnings");
 const { resolveEnsName } = require("../src/shared/ens");
 const { setRuntimeDebug } = require("../src/shared/log");
@@ -90,3 +94,12 @@ test("the balance refresh", async () => {
     expectFailureLoggedWithoutKey("ETH balance failed");
     expectFailureLoggedWithoutKey("ENS reverse failed");
 });
+
+// The lookup's first line, at debug level, names the RPC endpoint; the check
+// of everything printed covers it too.
+test("the token lookup", async () => {
+    await expect(lookupTokenInfo(ADDRESS, RPC_URL, "mainnet")).rejects.toThrow(
+        "Not a valid ERC-20 token",
+    );
+    expectFailureLoggedWithoutKey("symbol() failed:");
+});

tests/sendMax.test.js

@@ -0,0 +1,530 @@
+// The Send screen's "Max" control
+// (https://git.eeqj.de/sneak/AutistMask/issues/198).
+//
+// For ETH it fills in the exact balance minus the fee reserve the
+// confirmation screen's balance check gates on, never the four-decimal balance
+// the Send screen shows; the confirmation screen re-derives that amount from
+// its own estimate, and signs with that estimate's fee fields. For a token it
+// fills in the whole balance, and the check that ETH covers the fee still
+// applies.
+//
+// Driven through the real refreshBalances(), Send screen and confirmation
+// screen, Sign & Send included, with only the node, the explorer and the DOM
+// stubbed.
+
+"use strict";
+
+// What the stub node answers, and the signed transactions it was handed.
+const mockNode = {
+    balanceWei: 0n,
+    feeData: null,
+    broadcast: [],
+};
+
+// The token rows the stub explorer reports for the address.
+const mockExplorer = { items: [] };
+
+jest.mock("ethers", () => {
+    const actual = jest.requireActual("ethers");
+    class StubProvider {
+        async getBalance() {
+            return mockNode.balanceWei;
+        }
+        async lookupAddress() {
+            return null;
+        }
+        async getFeeData() {
+            return mockNode.feeData;
+        }
+        async estimateGas() {
+            return 21000n;
+        }
+        async getCode() {
+            return "0x";
+        }
+        async getTransactionCount() {
+            return 1;
+        }
+        async getNetwork() {
+            return { chainId: 1n };
+        }
+        async broadcastTransaction(signed) {
+            mockNode.broadcast.push(signed);
+            return { hash: "0x" + "ab".repeat(32) };
+        }
+    }
+    return {
+        ...actual,
+        JsonRpcProvider: StubProvider,
+        Network: { from: () => ({}) },
+    };
+});
+
+jest.mock("../src/shared/log", () => ({
+    log: {
+        debugf: () => {},
+        infof: () => {},
+        warnf: () => {},
+        errorf: () => {},
+    },
+    // The explorer's token list, which refreshBalances() also fetches.
+    debugFetch: jest.fn(async () => ({
+        ok: true,
+        status: 200,
+        json: async () => mockExplorer.items,
+    })),
+    urlOrigin: () => "",
+    setRuntimeDebug: () => {},
+    isDebug: () => false,
+}));
+
+// The wait screen polls for a receipt; these tests stop at the broadcast.
+jest.mock("../src/popup/views/txStatus", () => ({
+    showWait: jest.fn(),
+    showError: jest.fn(),
+}));
+
+// The confirmation screen's Etherscan label lookup is the only fetch() these
+// screens make; it fails, as it does offline.
+global.fetch = jest.fn(() => {
+    throw new Error("tests must not perform network requests");
+});
+
+const { makeStorageStub } = require("./support/storageStub");
+global.chrome = { storage: makeStorageStub(), runtime: { sendMessage() {} } };
+
+// A stub DOM: every id resolves to a recording element.
+const elements = new Map();
+
+function makeEl(id) {
+    const handlers = new Map();
+    return {
+        id,
+        textContent: "",
+        innerHTML: "",
+        value: "",
+        disabled: false,
+        style: {},
+        dataset: {},
+        classList: {
+            add() {},
+            remove() {},
+            toggle() {},
+            contains: () => false,
+        },
+        handlers,
+        children: [],
+        addEventListener(name, fn) {
+            handlers.set(name, fn);
+        },
+        appendChild(child) {
+            this.children.push(child);
+            return child;
+        },
+        querySelectorAll: () => [],
+        querySelector: () => null,
+        remove() {},
+        focus() {},
+    };
+}
+
+global.document = {
+    getElementById(id) {
+        if (!elements.has(id)) elements.set(id, makeEl(id));
+        return elements.get(id);
+    },
+    createElement: (tag) => makeEl(tag),
+    body: { prepend() {}, appendChild() {} },
+    addEventListener() {},
+};
+global.navigator = { clipboard: { writeText() {} } };
+
+const { Transaction, Wallet, formatEther } = require("ethers");
+const { refreshBalances } = require("../src/shared/balances");
+const { encryptWithPassword } = require("../src/shared/vault");
+const { state } = require("../src/shared/state");
+const send = require("../src/popup/views/send");
+const confirmTx = require("../src/popup/views/confirmTx");
+
+const PRIVATE_KEY = "0x" + "11".repeat(32);
+const HOLDER = new Wallet(PRIVATE_KEY).address;
+const RECIPIENT = "0xC0FfEE0000000000000000000000000000c0fFEe";
+// A second address of the wallet, and a second recipient.
+const OTHER = "0x" + "e".repeat(40);
+const PASSWORD = "correct horse battery staple";
+
+const GWEI = 1000000000n;
+const GAS = 21000n;
+
+// The Send screen shows this balance as 1.2345 ETH.
+const BALANCE_WEI = 1234567890123456789n;
+
+// A token the bundled list does not know, with enough holders to be listed.
+const TOKEN = "0x" + "d".repeat(40);
+
+// Fee data whose reserve is 21000 gas at `maxFeePerGas`. The expected cost,
+// at gasPrice, is lower, as it is on mainnet.
+function fees(maxFeePerGas) {
+    return {
+        maxFeePerGas,
+        maxPriorityFeePerGas: GWEI,
+        gasPrice: maxFeePerGas / 2n,
+    };
+}
+
+// The balance minus a reserve of 21000 gas at `maxFeePerGas`.
+function maxAfter(maxFeePerGas) {
+    return formatEther(BALANCE_WEI - GAS * maxFeePerGas);
+}
+
+function el(id) {
+    return global.document.getElementById(id);
+}
+
+function text(id) {
+    return el(id).textContent;
+}
+
+// The ETH balance the node reports and the token rows the explorer reports,
+// fetched and stored exactly where the popup stores them.
+async function refreshWith(balanceWei, tokenItems = []) {
+    mockNode.balanceWei = balanceWei;
+    mockExplorer.items = tokenItems;
+    state.wallets = [
+        {
+            type: "key",
+            name: "Wallet 1",
+            encryptedSecret: await encryptWithPassword(PRIVATE_KEY, PASSWORD),
+            addresses: [{ address: HOLDER }],
+        },
+    ];
+    state.selectedWallet = 0;
+    state.selectedAddress = 0;
+    await refreshBalances(
+        state.wallets,
+        "https://rpc.example.invalid",
+        "https://blockscout.example/api/v2",
+        state.trackedTokens,
+        "mainnet",
+    );
+}
+
+function tokenRow(value, decimals = "18") {
+    return {
+        value: String(value),
+        token: {
+            type: "ERC-20",
+            address_hash: TOKEN,
+            symbol: "TOK",
+            name: "Token",
+            decimals,
+            holders_count: "50000",
+        },
+    };
+}
+
+// The confirmation screen Review leads to, once shown.
+let confirmed = null;
+
+// Open the Send screen for `token` ("ETH" or a token address), with the
+// recipient entered.
+function openSend(token = "ETH") {
+    send.init({ showConfirmTx: (info) => (confirmed = info) });
+    confirmTx.init({});
+    send.resetSendValidation();
+    state.currentView = "send";
+    state.selectedToken = token;
+    el("send-to").value = RECIPIENT;
+    el("send-amount").value = "";
+}
+
+async function pressMax() {
+    await el("btn-send-max").handlers.get("click")();
+}
+
+// Press Review and show the confirmation screen with its fee estimate settled.
+async function review() {
+    await el("btn-send-review").handlers.get("click")();
+    confirmTx.show(confirmed);
+    await settle();
+}
+
+// show() starts the fee estimate without awaiting it; this lets it settle.
+async function settle() {
+    for (let i = 0; i < 10; i++) await new Promise((r) => setTimeout(r, 0));
+}
+
+function canSend() {
+    return !el("btn-confirm-send").disabled;
+}
+
+beforeEach(() => {
+    elements.clear();
+    confirmed = null;
+    state.selectedToken = null;
+    state.trackedTokens = [];
+    state.fraudContracts = [];
+    state.currentView = null;
+    mockNode.feeData = fees(20n * GWEI);
+    mockNode.broadcast = [];
+});
+
+describe("Max on an ETH send", () => {
+    test("fills in the exact balance minus the fee reserve", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        send.updateSendBalance();
+        expect(text("send-balance")).toBe("Current balance: 1.2345 ETH");
+        await pressMax();
+        // 1.234567890123456789 - 21000 * 20 gwei.
+        expect(el("send-amount").value).toBe("1.234147890123456789");
+    });
+
+    test("leaves exactly the fee reserve behind, and the confirmation screen enables Send", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        await pressMax();
+        await review();
+        expect(text("confirm-amount")).toBe(maxAfter(20n * GWEI) + " ETH");
+        expect(el("confirm-errors").innerHTML).toBe("");
+        expect(el("confirm-amount-fee-error").style.visibility).toBe("hidden");
+        expect(canSend()).toBe(true);
+    });
+
+    test("re-derives the amount when the fee estimate changes", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        await pressMax();
+        expect(el("send-amount").value).toBe(maxAfter(20n * GWEI));
+
+        // The fee rises between Max and the confirmation screen's estimate.
+        // Kept, the Send screen's amount would be refused for want of funds.
+        mockNode.feeData = fees(30n * GWEI);
+        await review();
+        expect(text("confirm-amount")).toBe(maxAfter(30n * GWEI) + " ETH");
+        expect(canSend()).toBe(true);
+
+        // And falls when the screen is shown again, as on reopening the popup.
+        mockNode.feeData = fees(10n * GWEI);
+        confirmTx.restore();
+        await settle();
+        expect(text("confirm-amount")).toBe(maxAfter(10n * GWEI) + " ETH");
+        expect(canSend()).toBe(true);
+    });
+
+    test("is signed with the fee its amount leaves behind", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        await pressMax();
+        await review();
+        // The fee the node quotes rises after the estimate. Fetched afresh
+        // at signing, it would make amount plus fee more than the balance.
+        mockNode.feeData = fees(25n * GWEI);
+        el("confirm-tx-password").value = PASSWORD;
+        await el("btn-confirm-send").handlers.get("click")();
+
+        expect(mockNode.broadcast).toHaveLength(1);
+        const tx = Transaction.from(mockNode.broadcast[0]);
+        expect(tx.to).toBe(RECIPIENT);
+        expect(tx.maxFeePerGas).toBe(20n * GWEI);
+        expect(tx.value + tx.gasLimit * tx.maxFeePerGas).toBe(BALANCE_WEI);
+    });
+
+    test("says so instead of filling in an amount when the balance does not cover the fee", async () => {
+        // 0.0001 ETH against a reserve of 0.00042 ETH.
+        await refreshWith(100000000000000n);
+        openSend();
+        await pressMax();
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe(
+            "Your balance does not cover the network fee.",
+        );
+    });
+
+    test("asks for the recipient first, since the fee depends on it", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        el("send-to").value = "";
+        await pressMax();
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe(
+            "Please enter a recipient address first.",
+        );
+    });
+
+    // Holds the node's fee answer, so Max's estimate is still running, until
+    // the returned function is called.
+    function holdFeeEstimate() {
+        let release;
+        mockNode.feeData = new Promise((resolve) => {
+            release = () => resolve(fees(20n * GWEI));
+        });
+        return release;
+    }
+
+    test.each([
+        ["the same address", 0],
+        ["another address", 1],
+    ])(
+        "fills nothing in once Send was left and opened again for %s while the fee was estimated",
+        async (_, addressIndex) => {
+            await refreshWith(BALANCE_WEI);
+            state.wallets[0].addresses.push({
+                address: OTHER,
+                balance: "2.0",
+                tokenBalances: [],
+            });
+            openSend();
+            const release = holdFeeEstimate();
+            const pressed = pressMax();
+
+            // Back, then Send again as home.js opens it, with the same
+            // recipient typed in again.
+            state.selectedAddress = addressIndex;
+            el("send-to").value = "";
+            el("send-amount").value = "";
+            send.resetSendValidation();
+            el("send-to").value = RECIPIENT;
+
+            release();
+            await pressed;
+            expect(el("send-amount").value).toBe("");
+            expect(text("flash-msg")).toBe("");
+        },
+    );
+
+    test("fills nothing in and says nothing once Send was left while the fee was estimated", async () => {
+        // 0.0001 ETH, which does not cover the fee: a result that landed
+        // would say so on whichever screen is shown.
+        await refreshWith(100000000000000n);
+        openSend();
+        const release = holdFeeEstimate();
+        const pressed = pressMax();
+        state.currentView = "home";
+        release();
+        await pressed;
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe("");
+    });
+
+    test("fills nothing in when the recipient changed while the fee was estimated", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        const release = holdFeeEstimate();
+        const pressed = pressMax();
+        el("send-to").value = OTHER;
+        release();
+        await pressed;
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe("");
+    });
+
+    test("fills nothing in when the holding was changed while the fee was estimated", async () => {
+        await refreshWith(BALANCE_WEI, [tokenRow(10n ** 18n)]);
+        // Opened from the home screen, where the dropdown picks the holding.
+        openSend(null);
+        el("send-token").value = "ETH";
+        const release = holdFeeEstimate();
+        const pressed = pressMax();
+        el("send-token").value = TOKEN;
+        el("send-token").handlers.get("change")();
+        release();
+        await pressed;
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe("");
+    });
+
+    test("keeps an amount typed while the fee was estimated", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        const release = holdFeeEstimate();
+        const pressed = pressMax();
+        el("send-amount").value = "0.5";
+        el("send-amount").handlers.get("input")();
+        release();
+        await pressed;
+        expect(el("send-amount").value).toBe("0.5");
+        expect(text("flash-msg")).toBe("");
+    });
+
+    test("fills in once the held fee estimate arrives with nothing changed", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        const release = holdFeeEstimate();
+        const pressed = pressMax();
+        release();
+        await pressed;
+        expect(el("send-amount").value).toBe(maxAfter(20n * GWEI));
+    });
+
+    test("typed over, is an ordinary amount the confirmation screen keeps", async () => {
+        await refreshWith(BALANCE_WEI);
+        openSend();
+        await pressMax();
+        el("send-amount").value = "0.5";
+        el("send-amount").handlers.get("input")();
+        mockNode.feeData = fees(30n * GWEI);
+        await review();
+        expect(text("confirm-amount")).toBe("0.5 ETH");
+    });
+});
+
+describe("Max on a token send", () => {
+    // 1234.567890123456789012 TOK; the Send screen shows 1234.5678.
+    const TOKEN_UNITS = 1234567890123456789012n;
+
+    test("fills in the whole token balance", async () => {
+        await refreshWith(BALANCE_WEI, [tokenRow(TOKEN_UNITS)]);
+        openSend(TOKEN);
+        await pressMax();
+        expect(el("send-amount").value).toBe("1234.567890123456789012");
+        await review();
+        expect(text("confirm-amount")).toBe("1234.567890123456789012 TOK");
+        expect(canSend()).toBe(true);
+    });
+
+    test("of a token with more than 18 decimal places, fills in the balance cut down to the 18 the confirmation screen accepts", async () => {
+        // 1234.567890123456789012999999 TOK at 24 decimal places.
+        await refreshWith(BALANCE_WEI, [
+            tokenRow(1234567890123456789012999999n, "24"),
+        ]);
+        openSend(TOKEN);
+        await pressMax();
+        expect(el("send-amount").value).toBe("1234.567890123456789012");
+        await review();
+        expect(text("confirm-amount")).toBe("1234.567890123456789012 TOK");
+        expect(canSend()).toBe(true);
+    });
+
+    test("is still refused when ETH cannot cover the fee", async () => {
+        await refreshWith(0n, [tokenRow(TOKEN_UNITS)]);
+        openSend(TOKEN);
+        await pressMax();
+        expect(el("send-amount").value).toBe("1234.567890123456789012");
+        await review();
+        expect(el("confirm-gas-error").style.visibility).toBe("visible");
+        expect(canSend()).toBe(false);
+    });
+
+    test("says so when the token balance is unknown", async () => {
+        // No scale from the explorer, the bundled list or a tracked token.
+        const row = tokenRow(TOKEN_UNITS);
+        delete row.token.decimals;
+        await refreshWith(BALANCE_WEI, [row]);
+        openSend(TOKEN);
+        await pressMax();
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe("This token's balance is unknown.");
+    });
+
+    test("says so when the token balance is zero", async () => {
+        state.trackedTokens = [
+            { address: TOKEN, symbol: "TOK", name: "Token", decimals: 18 },
+        ];
+        await refreshWith(BALANCE_WEI, [tokenRow(0n)]);
+        openSend(TOKEN);
+        await pressMax();
+        expect(el("send-amount").value).toBe("");
+        expect(text("flash-msg")).toBe("This token's balance is zero.");
+    });
+});

tests/settingsEndpointCheck.test.js

@@ -0,0 +1,148 @@
+// What reaches the console when an endpoint check in Settings fails.
+//
+// fetch refuses a URL with a user name and password in it, or one it cannot
+// parse, with an error whose message carries the whole URL: the password, and
+// any API key in the path or query string. The checks behind the RPC and
+// Blockscout Save buttons printed that message
+// (https://git.eeqj.de/sneak/AutistMask/issues/410); they now name the
+// endpoint by its origin.
+//
+// The real fetch runs; it throws before making any request. Debug mode is on,
+// so every log level is printed.
+
+const SECRETS = ["SECRETPASS789", "PATHKEY123", "QUERYTOKEN456"];
+const RPC_WITH_PASSWORD =
+    "https://user:SECRETPASS789@rpc.example.invalid/v3/PATHKEY123?token=QUERYTOKEN456";
+// Port 99999 is out of range, so the URL does not parse.
+const RPC_UNPARSEABLE =
+    "https://rpc.example.invalid:99999/v3/PATHKEY123?token=QUERYTOKEN456";
+const BLOCKSCOUT_WITH_PASSWORD =
+    "https://user:SECRETPASS789@explorer.example.invalid/PATHKEY123/api/v2";
+
+const SAVED_RPC = "https://saved-rpc.example.invalid";
+const SAVED_BLOCKSCOUT = "https://saved-explorer.example.invalid/api/v2";
+
+let elements;
+let flashes;
+let printed;
+let state;
+
+// A stand-in for one DOM node: enough of an element for init() to set
+// properties on it and hang listeners off it.
+function fakeElement() {
+    return {
+        value: "",
+        checked: false,
+        textContent: "",
+        href: "",
+        style: {},
+        dataset: {},
+        classList: { add() {}, remove() {} },
+        listeners: {},
+        addEventListener(event, handler) {
+            this.listeners[event] = handler;
+        },
+        querySelectorAll: () => [],
+    };
+}
+
+function element(id) {
+    return (elements[id] ||= fakeElement());
+}
+
+function loadSettingsView() {
+    elements = {};
+    flashes = [];
+
+    jest.resetModules();
+
+    jest.doMock("../src/popup/views/helpers", () => ({
+        $: element,
+        showView: () => {},
+        updateDebugBanner: () => {},
+        showFlash: (msg) => flashes.push(msg),
+        escapeHtml: (s) => s,
+        flashCopyFeedback: () => {},
+        goBack: () => {},
+        pushCurrentView: () => {},
+        onViewLeave: () => {},
+        VIEWS: [],
+    }));
+
+    state = require("../src/shared/state").state;
+    state.rpcUrl = SAVED_RPC;
+    state.blockscoutUrl = SAVED_BLOCKSCOUT;
+    require("../src/shared/log").setRuntimeDebug(true);
+
+    require("../src/popup/views/settings").init({});
+}
+
+async function save(fieldId, buttonId, typed) {
+    element(fieldId).value = typed;
+    await element(buttonId).listeners.click();
+}
+
+// The check failed, nothing was saved, and nothing printed carries the
+// password or the key.
+function expectFailedWithoutSecrets(label) {
+    expect(flashes).toContain("Could not reach endpoint.");
+    expect(state.rpcUrl).toBe(SAVED_RPC);
+    expect(state.blockscoutUrl).toBe(SAVED_BLOCKSCOUT);
+    const line = printed.find((text) => text.includes(label));
+    expect(line).toBeDefined();
+    const all = printed.join("\n");
+    for (const secret of SECRETS) {
+        expect(all).not.toContain(secret);
+    }
+    return line;
+}
+
+beforeEach(() => {
+    printed = [];
+    for (const method of ["log", "warn", "error"]) {
+        jest.spyOn(console, method).mockImplementation((...args) => {
+            printed.push(args.map(String).join(" "));
+        });
+    }
+    globalThis.chrome = {
+        runtime: { sendMessage: () => {} },
+        storage: { local: { get: async () => ({}), set: async () => {} } },
+    };
+});
+
+afterEach(() => {
+    jest.dontMock("../src/popup/views/helpers");
+    delete globalThis.chrome;
+    jest.restoreAllMocks();
+});
+
+test("fetch puts the whole URL in the error it throws for such a URL", async () => {
+    for (const url of [RPC_WITH_PASSWORD, RPC_UNPARSEABLE]) {
+        const error = await fetch(url).catch((e) => e);
+        expect(error.message).toContain("PATHKEY123");
+    }
+});
+
+test("the RPC check of a URL with a user name and password", async () => {
+    loadSettingsView();
+    await save("settings-rpc", "btn-save-rpc", RPC_WITH_PASSWORD);
+    const line = expectFailedWithoutSecrets("RPC validation fetch failed");
+    expect(line).toContain("https://rpc.example.invalid");
+});
+
+test("the RPC check of a URL that does not parse", async () => {
+    loadSettingsView();
+    await save("settings-rpc", "btn-save-rpc", RPC_UNPARSEABLE);
+    expectFailedWithoutSecrets("RPC validation fetch failed");
+});
+
+test("the Blockscout check of a URL with a user name and password", async () => {
+    loadSettingsView();
+    await save(
+        "settings-blockscout",
+        "btn-save-blockscout",
+        BLOCKSCOUT_WITH_PASSWORD,
+    );
+    const line = expectFailedWithoutSecrets("Blockscout validation failed");
+    expect(line).toContain("https://explorer.example.invalid");
+});

tests/stateMerge.test.js

@@ -423,3 +423,80 @@ describe("two wallets independently created with a colliding identity", () => {
         expect(secrets).toContain("secret-b");
     });
 });
+
+// showView() saves on every navigation without waiting, so the user can change
+// something while that save is still waiting on storage. The change is followed
+// by its own saveState(), which runs after the first save; it must be stored
+// (https://git.eeqj.de/sneak/AutistMask/issues/448).
+describe("a change made while an earlier save from the same page is running", () => {
+    // Runs `change` inside the next call to `op` (the stub's get or set),
+    // before that call does its work.
+    function runInside(op, change) {
+        const real = op.getMockImplementation();
+        op.mockImplementationOnce(async (arg) => {
+            change();
+            return real(arg);
+        });
+    }
+
+    test("a network switched during the earlier save's read is stored", async () => {
+        const storage = makeStorageStub({
+            autistmask: { wallets: [W1], networkId: "sepolia" },
+        });
+        const { state, saveState, loadState } = loadPage(storage).state;
+        await loadState();
+
+        let queued;
+        runInside(storage.get, () => {
+            state.networkId = "mainnet";
+            queued = saveState();
+        });
+        state.theme = "dark";
+        await saveState();
+        await queued;
+
+        const stored = storage.read("autistmask");
+        expect(stored.theme).toBe("dark");
+        expect(stored.networkId).toBe("mainnet");
+    });
+
+    test("a wallet added during the earlier save's read is stored", async () => {
+        const storage = makeStorageStub({ autistmask: { wallets: [W1] } });
+        const { state, saveState, loadState } = loadPage(storage).state;
+        await loadState();
+
+        let queued;
+        runInside(storage.get, () => {
+            state.wallets.push(W2);
+            queued = saveState();
+        });
+        await saveState();
+        await queued;
+
+        const stored = storage.read("autistmask");
+        expect(stored.wallets.map((w) => w.encryptedSecret)).toEqual([
+            "secret-one",
+            "secret-two",
+        ]);
+    });
+
+    test("a wallet added during the earlier save's write is stored", async () => {
+        const storage = makeStorageStub({ autistmask: { wallets: [W1] } });
+        const { state, saveState, loadState } = loadPage(storage).state;
+        await loadState();
+
+        let queued;
+        runInside(storage.set, () => {
+            state.wallets.push(W2);
+            queued = saveState();
+        });
+        await saveState();
+        await queued;
+
+        const stored = storage.read("autistmask");
+        expect(stored.wallets.map((w) => w.encryptedSecret)).toEqual([
+            "secret-one",
+            "secret-two",
+        ]);
+    });
+});

tests/stateRecovery.test.js

@@ -148,6 +148,173 @@ describe("the destructive reset on the recovery screen", () => {
     });
 });
 
+describe("a popup already open when the stored profile becomes unreadable", () => {
+    // https://git.eeqj.de/sneak/AutistMask/issues/373. The popup used to stay
+    // on the wallet list with the last good balances, and only a reopen
+    // reached the recovery screen.
+    test("moves to the recovery screen at its next refresh", async () => {
+        const env = await bootPopup(unversionedValidProfile());
+        expect(env.visibleViews()).toEqual(["main"]);
+
+        env.storage.write("autistmask", CORRUPT_BLOBS[0].blob);
+        await env.tick();
+
+        expect(env.visibleViews()).toEqual(["state-recovery"]);
+        expect(env.text("state-recovery-problem").length).toBeGreaterThan(10);
+        expect(env.hidden("btn-settings")).toBe(true);
+        expect(env.storage.read("autistmask")).toEqual(CORRUPT_BLOBS[0].blob);
+    });
+
+    test("stops the ten-second refresh", async () => {
+        const env = await bootPopup(unversionedValidProfile());
+        env.storage.write("autistmask", CORRUPT_BLOBS[0].blob);
+        await env.tick();
+        const { refreshBalances } = require("../src/shared/balances");
+        const calls = refreshBalances.mock.calls.length;
+
+        await env.tick();
+
+        expect(refreshBalances).toHaveBeenCalledTimes(calls);
+    });
+
+    test("a later save does not clear what the user exported or typed", async () => {
+        const env = await bootPopup(unversionedValidProfile());
+        env.storage.write("autistmask", CORRUPT_BLOBS[2].blob);
+        await env.tick();
+
+        await env.click("btn-state-recovery-export");
+        env.node("state-recovery-reset-input").value = "erase my";
+        // Such as the save of a refresh already in flight when the screen
+        // went up.
+        const { saveState } = require("../src/shared/state");
+        await expect(saveState()).rejects.toThrow();
+        await env.settle();
+
+        expect(env.visibleViews()).toEqual(["state-recovery"]);
+        expect(env.hidden("state-recovery-blob")).toBe(false);
+        expect(env.value("state-recovery-reset-input")).toBe("erase my");
+    });
+
+    // The record can become readable again under this popup, erased from the
+    // recovery screen of another window, so a save from this one can succeed.
+    test("a popup opened after the record is erased elsewhere shows a screen", async () => {
+        const env = await bootPopup(unversionedValidProfile());
+        env.storage.write("autistmask", CORRUPT_BLOBS[0].blob);
+        await env.tick();
+        expect(env.visibleViews()).toEqual(["state-recovery"]);
+
+        await env.storage.remove("autistmask");
+        const { saveState } = require("../src/shared/state");
+        await saveState();
+
+        const reopened = await bootPopup(env.storage.read("autistmask"));
+        expect(reopened.visibleViews()).toEqual(["welcome"]);
+    });
+
+    test("a stored current view of the recovery screen does not blank the popup", async () => {
+        const env = await bootPopup(
+            unversionedValidProfile({ currentView: "state-recovery" }),
+        );
+        expect(env.visibleViews()).toEqual(["main"]);
+    });
+
+    test("a transaction wait that ends under it does not replace it", async () => {
+        const env = await bootPopup(
+            unversionedValidProfile({
+                currentView: "wait-tx",
+                viewData: {
+                    pendingWait: {
+                        hash: "0x1",
+                        txInfo: { to: ADDRESS, amount: "1", token: "ETH" },
+                        broadcastTime: Date.now(),
+                    },
+                },
+            }),
+        );
+        expect(env.visibleViews()).toEqual(["wait-tx"]);
+        env.storage.write("autistmask", CORRUPT_BLOBS[2].blob);
+        await env.tick();
+        await env.click("btn-state-recovery-export");
+        env.node("state-recovery-reset-input").value = "erase my";
+
+        // The test provider answers no receipt lookup, and six that fail in
+        // a row end the wait with an error.
+        for (let i = 0; i < 6; i++) await env.tick();
+
+        expect(env.text("error-tx-message")).toMatch(/could not be reached/);
+        expect(env.visibleViews()).toEqual(["state-recovery"]);
+        expect(env.hidden("state-recovery-blob")).toBe(false);
+        expect(env.value("state-recovery-reset-input")).toBe("erase my");
+    });
+
+    test("a storage read that fails once leaves the wallet list up", async () => {
+        const env = await bootPopup(unversionedValidProfile());
+
+        env.storage.local.get.mockRejectedValueOnce(
+            new Error("IO error: storage busy"),
+        );
+        await env.tick();
+
+        // Reported as a failed save, not mistaken for an unreadable profile.
+        expect(env.visibleViews()).toEqual(["main"]);
+        expect(env.node("save-failure-banner")).not.toBeNull();
+
+        await env.tick();
+        expect(env.visibleViews()).toEqual(["main"]);
+    });
+
+    // The screen it replaces is left as any navigation leaves it: the rules
+    // at the top of src/popup/views/showPhrase.js and exportPrivkey.js hold
+    // for this way off them too.
+    describe("from a screen holding a secret", () => {
+        const PHRASE =
+            "abandon abandon abandon abandon abandon abandon abandon" +
+            " abandon abandon abandon abandon about";
+
+        afterEach(() => jest.dontMock("../src/shared/vault"));
+
+        test("a recovery phrase on screen is wiped", async () => {
+            jest.doMock("../src/shared/vault", () => ({
+                decryptWithPassword: async () => PHRASE,
+            }));
+            const env = await bootPopup(unversionedValidProfile());
+            require("../src/popup/views/showPhrase").show(0);
+            env.node("show-phrase-password").value = "password";
+            await env.click("btn-show-phrase-reveal");
+            expect(env.text("show-phrase-value")).toBe(PHRASE);
+
+            env.storage.write("autistmask", CORRUPT_BLOBS[0].blob);
+            await env.tick();
+
+            expect(env.visibleViews()).toEqual(["state-recovery"]);
+            expect(env.text("show-phrase-value")).toBe("");
+        });
+
+        test("a private key still being decrypted is never written", async () => {
+            let answer;
+            jest.doMock("../src/shared/vault", () => ({
+                decryptWithPassword: () =>
+                    new Promise((resolve) => {
+                        answer = resolve;
+                    }),
+            }));
+            const env = await bootPopup(unversionedValidProfile());
+            require("../src/popup/views/exportPrivkey").show(0, 0);
+            env.node("export-privkey-password").value = "password";
+            const revealing = env.click("btn-export-privkey-confirm");
+
+            env.storage.write("autistmask", CORRUPT_BLOBS[0].blob);
+            await env.tick();
+            expect(env.visibleViews()).toEqual(["state-recovery"]);
+            expect(env.value("export-privkey-password")).toBe("");
+
+            answer(PHRASE);
+            await revealing;
+            expect(env.text("export-privkey-value")).toBe("");
+        });
+    });
+});
+
 describe("an unversioned profile that is perfectly valid", () => {
     // The upgrade case. Every install in the field is in this state, and the
     // popup must load it, not offer to wipe it.

tests/support/popupBoot.js

@@ -40,6 +40,10 @@ jest.doMock("libsodium-wrappers-sumo", () => sodium);
 jest.doMock("qrcode", () => QRCode);
 jest.doMock("ethereum-blockies-base64", () => makeBlockie);
 
+// Taken before any boot replaces them; see bootPopup().
+const realSetInterval = globalThis.setInterval;
+const realClearInterval = globalThis.clearInterval;
+
 const POPUP_HTML = fs.readFileSync(
     path.join(__dirname, "..", "..", "src", "popup", "index.html"),
     "utf8",
@@ -259,9 +263,12 @@ async function bootPopup(stored, options) {
         getProvider: () => ({}),
         scanForAddresses: jest.fn(async () => []),
     }));
+    // filterTransactions() answers in the real one's shape: Home,
+    // AddressDetail and AddressToken read both fields, and a bare list makes
+    // their transaction loading throw into a catch that only logs.
     jest.doMock("../../src/shared/transactions", () => ({
         fetchRecentTransactions: jest.fn(async () => []),
-        filterTransactions: () => [],
+        filterTransactions: () => ({ transactions: [], newFraudContracts: [] }),
     }));
 
     const storage =
@@ -292,9 +299,20 @@ async function bootPopup(stored, options) {
         }),
         addEventListener: () => {},
     };
-    // The 10s refresh loop init() starts would outlive the test.
+    // The ten-second refresh init() starts, and a transaction wait's timers,
-    const realSetInterval = globalThis.setInterval;
+    // would outlive the test. So every interval is recorded rather than
-    globalThis.setInterval = () => 0;
+    // started, clearInterval() removes it as a browser would, and tick() below
+    // runs the ones still set. Put back by cleanupPopup().
+    const intervals = new Map();
+    let lastId = 0;
+    globalThis.setInterval = (fn) => {
+        lastId += 1;
+        intervals.set(lastId, fn);
+        return lastId;
+    };
+    globalThis.clearInterval = (id) => {
+        intervals.delete(id);
+    };
 
     require("../../src/popup/index");
 
@@ -316,8 +334,6 @@ async function bootPopup(stored, options) {
     }
     await settle();
 
-    globalThis.setInterval = realSetInterval;
-
     return {
         storage,
         document,
@@ -337,6 +353,12 @@ async function bootPopup(stored, options) {
             for (const fn of fns) await fn();
             await settle();
         },
+        // Every interval still set runs once: the ten-second refresh, and a
+        // transaction wait's receipt poll and elapsed counter while one runs.
+        tick: async () => {
+            for (const fn of intervals.values()) await fn();
+            await settle();
+        },
         settle,
         // The view ids whose section is not hidden, as the audit measured them.
         visibleViews: () => {
@@ -354,6 +376,8 @@ function cleanupPopup() {
     delete globalThis.chrome;
     delete globalThis.document;
     delete globalThis.window;
+    globalThis.setInterval = realSetInterval;
+    globalThis.clearInterval = realClearInterval;
 }
 
 module.exports = {

tests/transactions.test.js

@@ -1219,7 +1219,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
 
     test("queries only the two Blockscout endpoints for the address", async () => {
         respondWith([], []);
-        await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(debugFetch).toHaveBeenCalledTimes(2);
         const urls = debugFetch.mock.calls.map((c) => c[0]);
         expect(urls).toContain(
@@ -1283,7 +1283,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
             ],
         );
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(txs).toHaveLength(1);
         const merged = txs[0];
         // The received leg (the swap output) supplies the display amount.
@@ -1320,7 +1320,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
             ],
         );
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(txs).toHaveLength(1);
         expect(txs[0].symbol).toBe("USDC");
         expect(txs[0].value).toBe("1500.5000");
@@ -1346,7 +1346,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
         });
         respondWith([], [leg("1000000"), leg("2000000")]);
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(txs).toHaveLength(1);
         // Keyed by hash plus contract, so the later leg wins.
         expect(txs[0].exactValue).toBe("2.0");
@@ -1386,7 +1386,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
             ],
         );
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(txs.map((t) => t.symbol).sort()).toEqual(["USDC", "WETH"]);
     });
 
@@ -1427,12 +1427,13 @@ describe("fetchRecentTransactions merge and dedup", () => {
             ],
         );
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(txs).toHaveLength(1);
         expect(txs[0].symbol).toBe("USDC");
         expect(txs[0].exactValue).toBe("1.0");
         expect(txs[0].direction).toBe("sent");
         expect(txs[0].contractAddress).toBe(USDC_CONTRACT);
+        expect(txs[0].chainId).toBe("0x1");
         // The surviving row is the token row, and the filters keep it.
         const kept = filterTransactions(txs, filters()).transactions;
         expect(kept).toHaveLength(1);
@@ -1452,10 +1453,46 @@ describe("fetchRecentTransactions merge and dedup", () => {
         });
         respondWith([item(6), item(8), item(7)], []);
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, 2);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1", 2);
         expect(txs.map((t) => t.blockNumber)).toEqual([21000008, 21000007]);
     });
 
+    // https://git.eeqj.de/sneak/AutistMask/issues/372: the caller hands in
+    // the chain id of the network the explorer serves. Every entry carries
+    // it, and a native entry is labelled with that network's nativeCurrency.
+    test("a native entry is labelled by the chain id handed in", async () => {
+        respondWith(
+            [
+                {
+                    hash: "0x" + "a".repeat(64),
+                    block_number: 21000090,
+                    timestamp: TS,
+                    from: { hash: ORDINARY_PEER },
+                    to: { hash: VICTIM, is_contract: false },
+                    value: "10000000000000000",
+                    method: null,
+                    status: "ok",
+                },
+            ],
+            [],
+        );
+        const sepolia = await fetchRecentTransactions(
+            VICTIM,
+            BLOCKSCOUT,
+            "0xaa36a7",
+        );
+        expect(sepolia[0].symbol).toBe("SepoliaETH");
+        expect(sepolia[0].value).toBe("0.0100");
+        expect(sepolia[0].chainId).toBe("0xaa36a7");
+        const mainnet = await fetchRecentTransactions(
+            VICTIM,
+            BLOCKSCOUT,
+            "0x1",
+        );
+        expect(mainnet[0].symbol).toBe("ETH");
+        expect(mainnet[0].chainId).toBe("0x1");
+    });
+
     test("the fake token transfer survives fetching and is then filtered", async () => {
         respondWith(
             [],
@@ -1476,7 +1513,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
             ],
         );
 
-        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
         expect(txs).toHaveLength(1);
         expect(txs[0].contractAddress).toBe(FAKE_ETH_CONTRACT);
         expect(txs[0].holders).toBe(0);
@@ -1515,19 +1552,31 @@ describe("fetchRecentTransactions merge and dedup", () => {
 
         test("an omitted holders_count parses to null", async () => {
             respondWith([], spamTransferWithToken(OMITTED));
-            const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+            const txs = await fetchRecentTransactions(
+                VICTIM,
+                BLOCKSCOUT,
+                "0x1",
+            );
             expect(txs[0].holders).toBeNull();
         });
 
         test("a null holders_count parses to null", async () => {
             respondWith([], spamTransferWithToken(NULLED));
-            const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+            const txs = await fetchRecentTransactions(
+                VICTIM,
+                BLOCKSCOUT,
+                "0x1",
+            );
             expect(txs[0].holders).toBeNull();
         });
 
         test("the transfer survives the low-holder filter", async () => {
             respondWith([], spamTransferWithToken(OMITTED));
-            const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+            const txs = await fetchRecentTransactions(
+                VICTIM,
+                BLOCKSCOUT,
+                "0x1",
+            );
             expect(filterTransactions(txs, filters()).transactions).toEqual(
                 txs,
             );
@@ -1539,7 +1588,11 @@ describe("fetchRecentTransactions merge and dedup", () => {
         // holder count is the only rule that can catch it.
         test('a reported holders_count of "0" still parses to 0 and is filtered', async () => {
             respondWith([], spamTransferWithToken(ZERO));
-            const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT);
+            const txs = await fetchRecentTransactions(
+                VICTIM,
+                BLOCKSCOUT,
+                "0x1",
+            );
             expect(txs[0].holders).toBe(0);
             expect(filterTransactions(txs, filters()).transactions).toEqual([]);
         });
@@ -1555,7 +1608,7 @@ describe("fetchRecentTransactions merge and dedup", () => {
             },
         }));
         await expect(
-            fetchRecentTransactions(VICTIM, BLOCKSCOUT),
+            fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1"),
         ).resolves.toEqual([]);
     });
 

tests/transferAmount.test.js

@@ -4,7 +4,7 @@
 // contract at signing time, with nothing comparing the two, so a token whose
 // on-chain scale differed signed an amount that was never displayed.
 
-const { parseUnits } = require("ethers");
+const { formatUnits, parseUnits } = require("ethers");
 const {
     displayedDecimals,
     transferAmountUnits,
@@ -25,7 +25,17 @@ describe("displayedDecimals", () => {
         expect(displayedDecimals(MAX_DECIMALS)).toBe(MAX_DECIMALS);
     });
 
-    test("refuses anything that is not a uint8", () => {
+    // decimals() is a uint8, but formatUnits() and parseUnits() stop at 80
+    // places, so a larger scale cannot be shown or encoded
+    // (https://git.eeqj.de/sneak/AutistMask/issues/350).
+    test("accepts exactly the scales the formatter accepts", () => {
+        expect(() => formatUnits(1n, MAX_DECIMALS)).not.toThrow();
+        expect(() => parseUnits("1", MAX_DECIMALS)).not.toThrow();
+        expect(() => formatUnits(1n, MAX_DECIMALS + 1)).toThrow();
+        expect(() => parseUnits("1", MAX_DECIMALS + 1)).toThrow();
+    });
+
+    test("refuses anything that is not a uint8 the formatter accepts", () => {
         for (const bad of [
             null,
             undefined,

tests/txValidation.test.js

@@ -6,6 +6,8 @@ const {
     FEE_UNAVAILABLE,
     feeReserveWei,
     feeEstimateWei,
+    maxEthAmount,
+    maxTokenAmount,
     toFixedPoint,
     validateTransfer,
 } = require("../src/shared/txValidation");
@@ -306,6 +308,72 @@ describe("feeEstimateWei", () => {
     });
 });
 
+// The amount the Send screen's Max fills in for ETH: the exact balance, as
+// balances.js stores it, minus the fee reserve. Never the four-decimal balance
+// the Send screen shows.
+describe("maxEthAmount", () => {
+    // The Send screen shows this balance as 1.2345.
+    const BALANCE = "1.234567890123456789";
+
+    test("is the exact balance minus the fee, to the wei", () => {
+        expect(maxEthAmount(BALANCE, FEE)).toBe("1.234147890123456789");
+        expect(
+            parseEther(BALANCE) - parseEther(maxEthAmount(BALANCE, FEE)),
+        ).toBe(FEE);
+    });
+
+    test("passes validateTransfer with exactly the fee left behind", () => {
+        const r = validateTransfer({
+            isErc20: false,
+            amount: maxEthAmount(BALANCE, FEE),
+            ethBalance: BALANCE,
+            feeStatus: FEE_KNOWN,
+            feeWei: FEE,
+        });
+        expect(r).toEqual({ canSend: true, codes: [] });
+    });
+
+    test("is one wei when the balance is one wei more than the fee", () => {
+        expect(maxEthAmount("0.000420000000000001", FEE)).toBe(
+            "0.000000000000000001",
+        );
+    });
+
+    test("is null when the balance does not cover the fee", () => {
+        expect(maxEthAmount("0.0001", FEE)).toBe(null);
+        expect(maxEthAmount("0.0", FEE)).toBe(null);
+    });
+
+    test("is null when the balance covers the fee and nothing more", () => {
+        expect(maxEthAmount("0.00042", FEE)).toBe(null);
+    });
+
+    test("is null on a balance or fee it cannot do exact arithmetic on", () => {
+        expect(maxEthAmount(undefined, FEE)).toBe(null);
+        expect(maxEthAmount("not a number", FEE)).toBe(null);
+        expect(maxEthAmount(BALANCE, null)).toBe(null);
+        expect(maxEthAmount(BALANCE, -1n)).toBe(null);
+        expect(maxEthAmount(BALANCE, 420000000000000)).toBe(null);
+    });
+});
+
+// The amount the Send screen's Max fills in for a token.
+describe("maxTokenAmount", () => {
+    test("cuts a balance with more than 18 places down, never up", () => {
+        const amount = maxTokenAmount("1234.567890123456789012999999");
+        expect(amount).toBe("1234.567890123456789012");
+        expect(toFixedPoint(amount)).not.toBe(null);
+    });
+
+    test("leaves a balance with 18 places or fewer as it is", () => {
+        expect(maxTokenAmount("0.123456789012345678")).toBe(
+            "0.123456789012345678",
+        );
+        expect(maxTokenAmount("1.5")).toBe("1.5");
+        expect(maxTokenAmount("100")).toBe("100");
+    });
+});
+
 // Everything that is not a usable fee blocks exactly as FEE_UNAVAILABLE does.
 // Each of these previously returned { canSend: true, codes: [] } — counting no
 // fee at all, on a full-balance send, in the direction that lets money out.

tests/uniswap.test.js

@@ -554,6 +554,33 @@ describe("uniswap decoder", () => {
         );
     });
 
+    test("shows the deadline as a UTC date and time", () => {
+        const result = uniswap.decode(FIRST_SWAP_CALLDATA, ROUTER_ADDR);
+        expect(detail(result, "Deadline").value).toBe("2026-02-27 08:25:51");
+    });
+
+    // A JavaScript date cannot hold this deadline. It used to make the whole
+    // swap undecoded.
+    test("a deadline of the uint256 maximum is stated in words", () => {
+        const data = buildExecute(
+            "0x08", // V2_SWAP_EXACT_IN
+            [
+                encodeV2SwapExactIn(USER_ADDR, 1000000n, 500000000000000n, [
+                    USDT_ADDR,
+                    WETH_ADDR,
+                ]),
+            ],
+            2n ** 256n - 1n,
+        );
+
+        const result = uniswap.decode(data, ROUTER_ADDR);
+        expect(result).not.toBeNull();
+        expect(result.name).toBe("Swap USDT \u2192 WETH");
+        expect(detail(result, "Deadline").value).toBe(
+            "After 275760-09-13 00:00:00 (no deadline in practice)",
+        );
+    });
+
     test("formats permit amount when not unlimited", () => {
         const data = buildExecute(
             "0x0a",
@@ -831,6 +858,104 @@ describe("uniswap decoder", () => {
         expect(detail(result, "Min. received").value).toBe("0.9900 USDC");
     });
 
+    // https://git.eeqj.de/sneak/AutistMask/issues/415 — the router's V2
+    // exact-in reads an amountIn of zero as universal-router
+    // Constants.ALREADY_PAID: an earlier step sent the tokens to the pair, and
+    // the swap uses all of them. Against 375998b this read "0.0000 USDT".
+    test("a V2 exact-in already-paid amountIn is named, not printed as zero", () => {
+        const data = buildExecute(
+            "0x08",
+            [
+                encodeV2SwapExactIn(
+                    USER_ADDR,
+                    0n, // Constants.ALREADY_PAID
+                    500000000000000n,
+                    [USDT_ADDR, WETH_ADDR],
+                ),
+            ],
+            9999999999n,
+        );
+
+        const result = uniswap.decode(data, ROUTER_ADDR);
+        expect(result).not.toBeNull();
+
+        expect(detail(result, "Token In").value).toContain("USDT");
+        expect(detail(result, "Amount").value).toBe(
+            "Whatever an earlier step sent to the pair (V2 already paid)",
+        );
+        expect(detail(result, "Amount").rawValue).toBe(
+            "Whatever an earlier step sent to the pair (V2 already paid)",
+        );
+        expect(detail(result, "Min. received").value).toBe("0.0005 WETH");
+    });
+
+    // https://git.eeqj.de/sneak/AutistMask/issues/415 — the router passes a
+    // BALANCE_CHECK_ERC20 whenever the balance is at least minBalance, so a
+    // zero one guarantees nothing. Against 375998b it replaced the swap's
+    // output side: Token Out = USDC, Min. received = "None (no minimum
+    // guaranteed)".
+    test("a zero balance check keeps the minimum a swap step stated", () => {
+        const data = buildExecute(
+            solidityPacked(["uint8", "uint8"], [0x08, 0x0e]),
+            [
+                encodeV2SwapExactIn(USER_ADDR, 1000000n, 500000000000000n, [
+                    USDT_ADDR,
+                    WETH_ADDR,
+                ]),
+                encodeBalanceCheck(USER_ADDR, USDC_ADDR, 0n),
+            ],
+            9999999999n,
+        );
+
+        const result = uniswap.decode(data, ROUTER_ADDR);
+        expect(result).not.toBeNull();
+
+        expect(detail(result, "Token Out").value).toContain("WETH");
+        expect(detail(result, "Min. received").value).toBe("0.0005 WETH");
+    });
+
+    // A nonzero balance check still replaces the output side, as before.
+    test("a nonzero balance check replaces the minimum a swap step stated", () => {
+        const data = buildExecute(
+            solidityPacked(["uint8", "uint8"], [0x08, 0x0e]),
+            [
+                encodeV2SwapExactIn(USER_ADDR, 1000000n, 500000000000000n, [
+                    USDT_ADDR,
+                    WETH_ADDR,
+                ]),
+                encodeBalanceCheck(USER_ADDR, USDC_ADDR, 2000000n),
+            ],
+            9999999999n,
+        );
+
+        const result = uniswap.decode(data, ROUTER_ADDR);
+        expect(result).not.toBeNull();
+
+        expect(detail(result, "Token Out").value).toContain("USDC");
+        expect(detail(result, "Min. received").value).toBe("2.0000 USDC");
+    });
+
+    // With no minimum stated before it, a zero balance check is what sets the
+    // output side, and it guarantees nothing.
+    test("a zero balance check with no earlier minimum states no minimum", () => {
+        const data = buildExecute(
+            solidityPacked(["uint8", "uint8"], [0x0b, 0x0e]),
+            [
+                encodeWrapEth(ROUTER_ADDR, 1000000000000000000n),
+                encodeBalanceCheck(USER_ADDR, USDT_ADDR, 0n),
+            ],
+            9999999999n,
+        );
+
+        const result = uniswap.decode(data, ROUTER_ADDR);
+        expect(result).not.toBeNull();
+
+        expect(detail(result, "Token Out").value).toContain("USDT");
+        expect(detail(result, "Min. received").value).toBe(
+            "None (no minimum guaranteed)",
+        );
+    });
+
     // Pins what https://git.eeqj.de/sneak/AutistMask/pulls/356 changed without
     // testing: a non-swap execute() carrying only PERMIT2_PERMIT names no
     // output currency, so it says so and titles itself "Uniswap Swap" rather

tests/uniswapUnknownDecimals.test.js

@@ -126,6 +126,19 @@ describe("a swap of a token outside the bundled list", () => {
     test("a bundled token on the other side still formats", () => {
         expect(swapDetail(data(), "Min. received").value).toBe("0.5000 WETH");
     });
+
+    // A token added by hand carries whatever its decimals() returned, and a
+    // uint8 reaches 255, but formatUnits() throws above 80. The throw left the
+    // whole swap undecoded rather than refused
+    // (https://git.eeqj.de/sneak/AutistMask/issues/350).
+    test("refuses to format when the token reports more than 80 decimals", () => {
+        state.trackedTokens = [
+            { address: NOVEL, symbol: "NOVEL", decimals: 81 },
+        ];
+        expect(swapDetail(data(), "Amount").value).toBe(
+            "1000000000 base units (decimals unknown)",
+        );
+    });
 });
 
 describe("the Min. received line takes the same rule", () => {