fix: only the user switches the wallet's network (closes #408)

A connected site's wallet_switchEthereumChain request for the other
supported network now opens a prompt in its own window, through the
existing approval machinery, naming the site and both networks. The
network, endpoints, balances and caches change, and chainChanged is
sent, only when the user approves it; rejecting or closing the prompt
answers 4001. One such prompt per site at a time; a request for the
active network needs none. The approval window no longer shows the
connection prompt while it waits for the approval's description,
since both prompts answer on the same port.

Model: opus-5-5

Makefile

@@ -1,4 +1,4 @@
-.PHONY: bootstrap setup install test test-e2e test-e2e-firefox lint fmt fmt-check check check-censored docker hooks build build-debug package vendor-blocklist clean dev
+.PHONY: bootstrap setup install test test-e2e test-e2e-firefox lint fmt fmt-check check check-censored docker hooks build build-debug package vendor-blocklist icons clean dev
 
 # Standard targets are thin shims; the implementations live in script/
 # per the scripts-to-rule-them-all pattern (see the Entrypoints section
@@ -104,6 +104,13 @@ build-debug:
 vendor-blocklist:
 	@script/vendor-blocklist
 
+# Redraw the toolbar icons in icons/ from script/lib/icons.js, at every size
+# manifest/chrome.json declares, leaving alone a file that already holds the
+# drawn image. Commit the result with the drawing: tests/icons.test.js fails
+# while the two disagree.
+icons:
+	@node script/lib/icons.js
+
 clean:
 	@rm -rf dist/ release/
 

README.md

@@ -317,6 +317,11 @@ The Makefile shims to those. It also carries a few targets that have no
 - `make build-debug` — the same build with `AUTISTMASK_DEBUG=1`, verified as a
   debug build, and keeping its `dist/` on failure (see
   [Debug Builds](#debug-builds))
+- `make icons` — redraw the toolbar icons in `icons/` from
+  `script/lib/icons.js`, at every size `manifest/chrome.json` declares. A file
+  that already holds the drawn image, the same IHDR and every pixel, is left
+  untouched. Commit the files with the drawing: `make check` fails while their
+  image differs from what it draws
 - `make clean` — remove `dist/` and `release/`
 - `make dev` — run the build `make build` runs, without the checks that follow
   it, then run it again after every change to a file under `src/`, `manifest/`
@@ -334,7 +339,9 @@ There are two suites, one per browser, and they share no code. Chrome runs on
 Playwright; Firefox has its own WebDriver client, because Playwright cannot
 observe errors on a Firefox extension page at all — see
 [Firefox](#firefox-make-test-e2e-firefox) below. Both require docker, and both
-are outside `make check`.
+are outside `make check`. Neither opens the popup from the toolbar button: both
+load its page in an ordinary tab, so what the toolbar popup itself adds, its
+size and its closing when it loses focus, is covered by neither.
 
 ### Chrome (`make test-e2e`)
 
@@ -407,27 +414,51 @@ content script, the inpage provider, the background worker and the approval
 popup all have to work together. A local test page is served by the route
 handler on a reserved-TLD origin, gets `window.ethereum` from the shipped
 `MAIN`-world content script like any other page, and drives
-`eth_requestAccounts`, `personal_sign`, `eth_signTypedData_v4` and
-`eth_sendTransaction` through the real prompts. Every signature is recovered in
-the runner and compared against the active address, the transaction assertions
-run against the raw signed transaction captured at `eth_sendRawTransaction`
-rather than against anything the extension reported, rejecting each prompt is
-required to return a rejection to the page rather than hang or resolve, a prompt
-raised while another approval window has focus is required to open a window of
-its own, and the password is required to be absent from every message the
-approval window sends to the background — with the message that would carry it
-required to be present, so that check cannot pass by observing nothing. That
+`eth_requestAccounts`, `personal_sign`, `eth_signTypedData_v4`,
+`eth_sendTransaction` and `wallet_switchEthereumChain` through the real prompts.
+Every signature is recovered in the runner and compared against the active
+address, the transaction assertions run against the raw signed transaction
+captured at `eth_sendRawTransaction` rather than against anything the extension
+reported, rejecting each prompt is required to return a rejection to the page
+rather than hang or resolve, a network switch request is required to leave the
+stored network unchanged and send no `chainChanged` until it is approved, a
+prompt raised while another approval window has focus is required to open a
+window of its own, and the password is required to be absent from every message
+the approval window sends to the background — with the message that would carry
+it required to be present, so that check cannot pass by observing nothing. That
 last one is the standing floor under
 [#157](https://git.eeqj.de/sneak/AutistMask/issues/157).
 
-Two limits of that coverage, neither of them papered over. The RPC is stubbed
-throughout, so this is **not** a real dApp against a real network with real
-funds; that remains a human pass before 1.0.0. The site-connection prompt is
-raised through `chrome.action.openPopup()`, and headless Chromium's
-browser-action popup is not a page Playwright can see or click, so that one
-prompt is driven at the URL the extension itself puts on the action — the same
-page and the same approval id, but whether a real toolbar click shows it is not
-observable here.
+The limits of that coverage and of the rest of the Chrome suite, none of them
+papered over:
+
+- The RPC is stubbed throughout, so this is **not** a real dApp against a real
+  network with real funds; that remains a human pass before 1.0.0.
+- The site-connection prompt is raised through `chrome.action.openPopup()`, and
+  headless Chromium's browser-action popup is not a page Playwright can see or
+  click, so that one prompt is driven at the URL the extension itself puts on
+  the action — the same page and the same approval id, but whether a real
+  toolbar click shows it is not observable here.
+- Each site-connection request is made 1.5 seconds after the tab it will be
+  driven in is opened (`APPROVAL_TAB_SETTLE_MS` in `tests/e2e/run.js`), because
+  opening that tab closes the previous prompt's toolbar popup; a request made
+  just after that popup closes is not covered.
+- In the tests that approve a signature or a transaction, the approval window
+  runs with `chrome.runtime.sendMessage` wrapped to record what it sends, and in
+  the tests that reject a site connection the prompt gets a click listener that
+  records that Reject was pressed; neither changes what the window does.
+- The tap to copy test first grants clipboard permission to every page in the
+  browser, which the manifest does not ask for, so whether a real popup may
+  write to the clipboard on a click alone is not covered.
+- The layout tests for an over-long flash message and for the password error
+  lines write the text straight into the page instead of letting the popup's
+  code put it there, and the second brings each screen up by toggling its
+  `hidden` class rather than navigating to it; they cover the layout, not the
+  code that fills it.
+- Leaving the recovery phrase or private key screen while its decrypt runs is
+  forced by clicking Reveal and the settings gear in one page task, which a
+  person cannot do; the case a person can hit, the first decrypt after the popup
+  opens while libsodium is still loading, is not driven.
 
 Any test that drives a failure path on purpose declares the `console.error` it
 is about to provoke, via `errors.expect()`. That is not a mute: the declaration
@@ -441,8 +472,8 @@ collecting for a fixed grace period after the last test returns
 the context. A request whose _first_ dispatch falls after that window is never
 seen at all and cannot fail the run. In practice a request a test fires without
 awaiting reaches the route handler about 10ms later, and anything on a repeating
-timer gets observed on an earlier tick during the ~20s suite — but a one-shot
-call deliberately deferred past the window will escape.
+timer gets observed on an earlier tick during the suite — but a one-shot call
+deliberately deferred past the window will escape.
 
 That interception covers the MV3 background service worker as well as the popup
 page, which it does not by default — `script/test-e2e` sets
@@ -496,10 +527,11 @@ Chrome that ever changes this fails the run instead of passing it.
 `make test-e2e-firefox` builds `dist/firefox/` and drives the **real popup in a
 real Firefox**, installed as an unpacked MV2 temporary add-on via geckodriver.
 It covers popup load, the StateRecovery screen (the same cases as the Chrome
-suite), wallet creation through the UI, the Add Token screen, and the four dApp
-round trips — `eth_requestAccounts`, `personal_sign`, `eth_sendTransaction`, and
-a closed approval window rejecting with EIP-1193 4001 — driven through the real
-content script, background page and approval windows.
+suite), wallet creation through the UI, the Add Token screen, and the dApp round
+trips — `eth_requestAccounts`, `personal_sign`, `wallet_switchEthereumChain`
+rejected and then approved, `eth_sendTransaction`, and a closed approval window
+rejecting with EIP-1193 4001 — driven through the real content script,
+background page and approval windows.
 
 The suite lives in `tests/e2e/firefox/`. Its WebDriver client (`driver.js`) has
 **no npm dependencies at all**: it is built on global `fetch` and
@@ -574,25 +606,18 @@ without an `await`. Demonstrated, not assumed: a `throw` placed past the first
 and on Chrome (`pageerror`), with the rest of the run unaffected because the
 approval view had already rendered.
 
-One error is tolerated rather than fatal, listed in `ALLOWED_ERRORS` in
-`tests/e2e/firefox/run.js` with the issue that will delete it, and printed on
-every occurrence so the concession stays visible in the run output. It is
-Firefox reporting the site-approval popup's unawaited `sendMessage` settling
-after `window.close()` unloaded the context — the same teardown ordering as
-[#275](https://git.eeqj.de/sneak/AutistMask/issues/275), and unsuppressable from
-the calling code, because `BaseContext.wrapPromise` reports it whether or not a
-handler is attached. Errors are read from the privileged `nsIConsoleService` in
-Marionette's chrome context and filtered to non-warning entries whose
-`sourceName` is the extension origin. That mechanism is not a stylistic choice.
-WebDriver BiDi's `log.entryAdded` delivers **nothing** for extension pages: on a
-plain `http://` page it reports uncaught errors with stack traces, and on the
-`moz-extension://` popup it reports zero events, because Firefox's remote agent
-excludes extension browsing contexts from BiDi observation. Any harness built on
-Playwright-BiDi or Puppeteer-BiDi would therefore see nothing and report
-success, which is exactly the vacuous check this repo has already shipped twice.
-Do not migrate this suite to BiDi.
+Errors are read from the privileged `nsIConsoleService` in Marionette's chrome
+context and filtered to non-warning entries whose `sourceName` is the extension
+origin. That mechanism is not a stylistic choice. WebDriver BiDi's
+`log.entryAdded` delivers **nothing** for extension pages: on a plain `http://`
+page it reports uncaught errors with stack traces, and on the `moz-extension://`
+popup it reports zero events, because Firefox's remote agent excludes extension
+browsing contexts from BiDi observation. Any harness built on Playwright-BiDi or
+Puppeteer-BiDi would therefore see nothing and report success, which is exactly
+the vacuous check this repo has already shipped twice. Do not migrate this suite
+to BiDi.
 
-Two limits are worth knowing, both real differences from the Chrome suite:
+Three limits are worth knowing, all real differences from the Chrome suite:
 
 - **Error capture is poll-based, not event-streamed.** The console is drained at
   each step boundary, so an error is attributed to the step it was drained
@@ -609,24 +634,30 @@ Two limits are worth knowing, both real differences from the Chrome suite:
   and silently evicts the oldest, so more than 250 console messages between two
   drains destroys the excess unread. 400 throws inside one step are reported as
   exactly the newest 250, three runs running. That buffer is shared with
-  Firefox's own console noise; a clean run peaks at 4 of 250 at the install
-  drain and 0 at every later drain, so the three steps here have wide headroom,
-  but a step that logs heavily could evict unread errors. What poll-based costs
-  is location, not coverage: an error cannot be placed within a step the way the
-  Chrome suite's `pageerror` events place it.
+  Firefox's own console noise; a clean run, measured when the suite had three
+  steps (popup load, wallet creation and Add Token), peaked at 4 of 250 at the
+  install drain and 0 at every later drain, but a step that logs heavily could
+  evict unread errors. What poll-based costs is location, not coverage: an error
+  cannot be placed within a step the way the Chrome suite's `pageerror` events
+  place it.
 - **Almost nothing is stubbed, which inverts the coverage of network-dependent
   code.** The container still runs with `--network none`, so the run is offline
   and no request can escape. The one thing it can reach is the loopback fixture
   in `tests/e2e/firefox/dapp.js`, which serves the dApp page and a JSON-RPC node
   and which the extension's `rpcUrl` is pointed at for the dApp steps; a
   JSON-RPC method that fixture does not model fails the run rather than
-  answering `null`. Everything else — Blockscout, the price feed, the phishing
-  blocklist — has no fixture and simply fails, and the extension swallows its
-  own fetch failures, so only the _failure_ branches of that code are ever
-  executed. A `ReferenceError` in the success path of `renderTransactions`, or
-  of price rendering, passes this suite green. The offline run is also weaker
-  than the Chrome suite's interception for those calls: it proves nothing got
-  out, but it cannot report which requests were attempted.
+  answering `null`. Everything else, Blockscout and the price feed among it, has
+  no fixture and simply fails, and the extension swallows its own fetch
+  failures, so only the _failure_ branches of that code are ever executed. A
+  `ReferenceError` in the success path of `renderTransactions`, or of price
+  rendering, passes this suite green. The offline run is also weaker than the
+  Chrome suite's interception for those calls: it proves nothing got out, but it
+  cannot report which requests were attempted.
+- **The site-connection prompt always opens in a window of its own.** The
+  profile turns off `extensions.openPopupWithoutUserGesture.enabled`, so
+  `src/background/index.js` falls back from the toolbar popup, which WebDriver
+  cannot see, to `windows.create()`; the toolbar popup path is not covered on
+  Firefox.
 
 Neither `make test-e2e` nor `make test-e2e-firefox` is part of `make check` or
 `make test`. `REPO_POLICIES.md` caps `make test` at 60 seconds and a browser
@@ -1235,14 +1266,21 @@ path rather than on the home screen. Read the claim narrowly, as that file
 states it: what those boots prove is no structural dereference on the code paths
 a WHOLLY-CORRUPTED PROFILE takes, which is not every path a stored record takes.
 Not driven: any pairing of values the four slots do not produce, a view only
-forward navigation opens, anything behind a click, and everything a healthy
-profile reaches. Within that boundary the verdict is unconditional — if one of
-those boots leaves the popup unhealthy or off the view it stored, `make check`
-fails, including when it takes two corrupted fields at once, because the verdict
-is the combined boot and the per-field re-boot that names a culprit can only
-decorate the message. So does a field that gains a floor while its row still
-claims it has none, and so does a field added to `PERSISTED_FIELDS` with no row
-at all. The per-field justification that used to live in the header of
+forward navigation opens, anything behind a click or a timer, and, of what a
+healthy profile reaches, anything beyond its boot onto each view the popup can
+reopen onto. The fields the router does not read share a slot on each boot, so
+one of them truthy while another is falsy is reached only where the falsy slot
+pairs a field that cannot be falsy with one that is. Within that boundary the
+verdict is unconditional — if one of those boots leaves the popup unhealthy,
+`make check` fails, including when it takes two corrupted fields at once,
+because the verdict is the combined boot and the per-field re-boot that names a
+culprit can only decorate the message. The combined boot must also land on the
+view it stored, and each value driven only onto the restore path must land on
+its view, or fall back to Home, as its row declares; a field the router reads
+can legitimately change which view renders, so its own sweep is held to health
+alone. `make check` also fails on a field that gains a floor while its row still
+claims it has none, and on a field added to `PERSISTED_FIELDS` with no row at
+all. The per-field justification that used to live in the header of
 `src/shared/stateSchema.js` shipped a false claim in three consecutive changes,
 each caught only by a reviewer re-deriving thirty fields by hand.
 
@@ -1283,11 +1321,14 @@ behind a "···" menu.
 
 Navigation uses a stack model (like iOS): each forward action pushes the current
 screen onto `state.viewStack`, and "Back" pops it (`pushCurrentView()` and
-`goBack()` in `src/popup/views/helpers.js`). The root screen is either Welcome
-(no wallets) or Home (has wallets). Each screen below gives its view id in
-parentheses; the registry of view ids is the `VIEWS` array in
-`src/popup/views/helpers.js`, and the markup for a screen is the element with id
-`view-` plus that view id in `src/popup/index.html`.
+`goBack()` in `src/popup/views/helpers.js`). "Back" skips an entry for the
+screen already showing: ShowRecoveryPhrase and the two delete screens take
+themselves off the stack when left, so the Settings gear on one of them leaves
+Settings under Settings, and "Back" from there goes to the screen before
+Settings. The root screen is either Welcome (no wallets) or Home (has wallets).
+Each screen below gives its view id in parentheses; the registry of view ids is
+the `VIEWS` array in `src/popup/views/helpers.js`, and the markup for a screen
+is the element with id `view-` plus that view id in `src/popup/index.html`.
 
 Three elements sit outside the screens and are present on all of them: the title
 bar ("AutistMask by @sneak" plus the Settings gear), the flash message line
@@ -1413,14 +1454,17 @@ view would leave a wallet one click from deletion.
       without it, the lost-password route on DeleteWallet is the first they
       would hear of it. The hint line reserves its height, so switching tabs
       cannot move the password fields under the pointer.
-    - "Import" button
+    - "Import" button, with the error line beside it so that it adds no height
+      to a screen whose button already starts near the bottom of the popup
 - **Transitions**:
     - "Import" with a valid entry and a matching password of at least 12
       characters → creates the wallet, clears the navigation stack, and →
       **Home**. The phrase and xprv modes then scan for further used addresses
       and report the count as a flash message.
-    - "Import" with an invalid entry, a duplicate wallet or address, or a short
-      or mismatched password → flash message, no screen change
+    - "Import" with a missing, short or mismatched password → full-sentence
+      error on the error line, no screen change
+    - "Import" with an invalid entry or a duplicate wallet or address → flash
+      message, no screen change
     - "Back" → previous screen (Welcome, Home, or Settings)
 
 #### AddressDetail (`address`)
@@ -1459,8 +1503,8 @@ view would leave a wallet one click from deletion.
       copy)
     - Warning that anyone holding the private key can transfer all funds from
       the address
-    - Error line
-    - Password input and "Reveal" button, shown until the key is revealed
+    - Password input, error line and "Reveal" button, shown until the key is
+      revealed
     - The private key on a highlighted background, tap to copy, shown only after
       the password has been accepted
 - **Transitions**:
@@ -1479,6 +1523,14 @@ view would leave a wallet one click from deletion.
   route, including the Settings gear. A decrypt still running when the screen is
   left is discarded rather than written. The screen is not restorable, so
   reopening the popup lands on Home rather than back on the key.
+- **Clipboard**: tapping the key copies it to the clipboard, and the wallet
+  never clears the clipboard afterwards; leaving the screen wipes the key from
+  the page only. The clipboard is the user's, not the wallet's. Clearing it
+  would go against what the user expects, and by then they may have copied
+  something else vital that the clear would destroy. The user knows the key is
+  secret from the warning above the password input, which says that anyone with
+  it can access and transfer all funds from the address, and knows it is on the
+  clipboard because they copied it. From then on it is theirs to manage.
 
 #### AddressToken (`address-token`)
 
@@ -1734,7 +1786,9 @@ view would leave a wallet one click from deletion.
     - Display: "Show tracked tokens with zero balance" checkbox, "UTC
       Timestamps" checkbox, and a Theme selector (System / Light / Dark)
     - Network: network selector (Ethereum Mainnet / Sepolia Testnet); switching
-      resets the RPC and Blockscout endpoints to that network's defaults
+      resets the RPC and Blockscout endpoints to that network's defaults. The
+      network changes only here, or when the user approves a site's request on
+      **NetworkApproval**
     - Ethereum RPC: endpoint URL input + "Save" button (validated against
       `eth_chainId` before being saved)
     - Blockscout API: endpoint URL input + "Save" button (validated against
@@ -1790,8 +1844,8 @@ view would leave a wallet one click from deletion.
     - Wallet name
     - Warning box stating that anyone holding these words can take everything in
       the wallet, from any device, without the password
-    - Error line
-    - Password input + "Reveal" button, shown until the password is accepted
+    - Password input, error line and "Reveal" button, shown until the password
+      is accepted
     - The recovery phrase itself, in full and click-to-copy, shown only after a
       correct password and in place of the password prompt
 - **Transitions**:
@@ -1809,6 +1863,9 @@ view would leave a wallet one click from deletion.
   gear. A decrypt still running when the screen is left is discarded rather than
   written. The screen is not restorable, so reopening the popup lands on Home
   rather than back on the phrase.
+- **Clipboard**: tapping the phrase copies it, and the wallet never clears the
+  clipboard afterwards, for the reasons given under ExportPrivKey; here the
+  warning box above the password input is what tells the user it is secret.
 
 #### DeleteWallet (`delete-wallet-confirm`)
 
@@ -1817,8 +1874,8 @@ view would leave a wallet one click from deletion.
     - "Back" button, "Delete Wallet" heading
     - Warning naming the wallet and stating that deletion is permanent and any
       funds are unrecoverable without the recovery phrase
-    - Error line
     - Password input
+    - Error line
     - "Confirm Delete" button
     - An underlined "I have lost my password" control
 - **Transitions**:
@@ -2019,7 +2076,10 @@ view would leave a wallet one click from deletion.
   no window and takes no nonce, and the site can send it again once the pending
   one is answered. The window is centred on the browser window the user was last
   in; if that was another approval window, or the browser refuses the centred
-  position, the browser picks the position.
+  position, the browser picks the position. The network shown is the one the
+  transaction was populated on, and a site cannot switch it without the user:
+  its `wallet_switchEthereumChain` request changes the network only when the
+  user approves it on **NetworkApproval**.
 - **Elements**:
     - "Transaction Request" heading
     - Phishing warning banner (shown when the hostname is on the phishing
@@ -2110,6 +2170,39 @@ view would leave a wallet one click from deletion.
     - Popup window closed without answering → the request is rejected with
       EIP-1193 code 4001
 
+#### NetworkApproval (`approve-network`)
+
+- **When**: A connected website asks to switch the network with
+  `wallet_switchEthereumChain`, naming a supported network other than the active
+  one. Only the user switches the network: until the user approves the request
+  here, it changes nothing — not the network, the RPC and Blockscout endpoints,
+  the balances or the cached token data — and no page is sent `chainChanged`.
+  Opened the same way as TxApproval, in a separate popup window. Only one exists
+  per site at a time: a further switch request from a site whose switch request
+  is still unanswered is refused with EIP-1193 code `-32002` and opens no
+  window. A request naming the network already active is answered at once and
+  opens nothing; one naming an unsupported chain is refused with code `4902`,
+  and one from a site that is not connected with code `4100`.
+  `wallet_addEthereumChain` never switches the network.
+- **Elements**:
+    - "Network Switch Request" heading
+    - Phishing warning banner (shown when the hostname is on the phishing
+      blocklist)
+    - Site origin (bold, scheme and port included) + "wants to switch the
+      wallet's network."
+    - Current network: its name
+    - Requested network: its name
+    - A line saying that switching changes the network for the whole wallet and
+      for every site
+    - "Switch" / "Reject" buttons
+- **Transitions**:
+    - "Switch" → closes popup; the background switches the network as
+      **Settings** does, sends `chainChanged` to every open tab, and answers the
+      site with success
+    - "Reject" → closes popup; the site is answered with EIP-1193 code 4001 and
+      nothing changes
+    - Popup window closed without answering → the same as "Reject"
+
 #### StateRecovery (`state-recovery`)
 
 - **When**: the stored profile fails `assertStateUsable()`. At open, that is
@@ -2404,6 +2497,8 @@ logged.
 - Sign transactions requested by connected sites (`eth_sendTransaction`)
 - Sign messages (`personal_sign`, `eth_sign`)
 - Sign typed data (`eth_signTypedData_v4`, `eth_signTypedData`)
+- Switch network at a connected site's request, once the user approves it
+  (`wallet_switchEthereumChain`)
 - Human-readable transaction decoding (ERC-20, Uniswap Universal Router)
 - ETH/USD and token/USD price display
 - Configurable RPC endpoint and Blockscout API

TODO.md

@@ -23,28 +23,152 @@
 
 pre-1.0, working towards the 1.0.0 milestone. Tagged v0.1.0 on 2026-02-27. The
 milestone is in flight on `next`; its `next` -> `main` PR is
-[#190](https://git.eeqj.de/sneak/AutistMask/pulls/190). `make check` verified
-green on `next` at `e9fa8be` on 2026-08-10, and `make build` produces
-`dist/chrome/` and `dist/firefox/`, verified against the build's own receipt to
-hold exactly the regular files and symlinks that build emitted, with `DEBUG`
-compiled off.
+[#388](https://git.eeqj.de/sneak/AutistMask/pulls/388). `make build` produces
+`dist/chrome/` and `dist/firefox/` with `DEBUG` compiled off, and checks them
+against the build's own receipt to hold exactly the regular files and symlinks
+that build emitted.
 
 The backlog lives on the
 [Gitea tracker](https://git.eeqj.de/sneak/AutistMask/issues), which is
 authoritative; this file does not duplicate it. Full policy file set present.
 Real-browser end-to-end suites (`make test-e2e` for Chrome,
-`make test-e2e-firefox` for Firefox) sit alongside `make check`, which now does
-static analysis as well as formatting, and `.gitea/workflows/e2e.yml` runs both
-of them on every push.
+`make test-e2e-firefox` for Firefox) sit alongside `make check`, which runs the
+tests, static analysis and the formatting check, and `.gitea/workflows/e2e.yml`
+runs both of them on every push.
 
 # Next Step
 
-Pre-1.0 security review of the extension (key handling, DEBUG mode policy, RPC
-input validation) before any 1.0rc tag. Individual filed issues are parts of it,
-but the review is broader than any of them.
+Cut 1.0.0 once the
+[1.0.0 milestone](https://git.eeqj.de/sneak/AutistMask/milestone/6) is empty,
+then continue tagging as milestones land.
 
 # Completed Steps
 
+- 2026-10-07: A site can no longer switch the wallet's network by itself
+  ([#408](https://git.eeqj.de/sneak/AutistMask/issues/408)). A connected site's
+  `wallet_switchEthereumChain` request for the other supported network opens a
+  prompt in its own window, through the same approval machinery as the
+  transaction and signature prompts, naming the site, the current network and
+  the requested one. The network, its endpoints, the balances and the caches
+  change, and `chainChanged` is sent, only when the user approves it; rejecting
+  or closing the prompt answers 4001. One such prompt per site at a time. The
+  approval window no longer shows the connection prompt while it waits for the
+  background to describe the approval, because that prompt's "Allow" answers on
+  the same port as the new one. `tests/chainSwitchGate.test.js` and both browser
+  suites drive the prompt.
+
+- 2026-10-07: Two holes in what `tests/persistedFieldContract.test.js` checks
+  are closed ([#379](https://git.eeqj.de/sneak/AutistMask/issues/379)). The
+  check that every swept field is driven both truthy and falsy counts only
+  `hostile` and `falsy` values, which the sweep drives onto every restorable
+  view, and no longer a `hostileRestore` value, which reaches only the views its
+  entry names; the stale index 5 moves into `hostile` for `selectedWallet` and
+  `selectedAddress`, as the one value of either still truthy after the floor.
+  Each `hostileRestore` entry declares whether its boot lands on its view or
+  falls back to Home, and is held to it. The limits that remain, fields that
+  share a slot on one boot and anything no stored record reaches by itself, are
+  restated as built in the file's header and the README, which now also say
+  which boots are held to where the popup lands and that a healthy profile is
+  booted onto every restorable view.
+
+- 2026-10-07: Every password error in the popup is shown the same way
+  ([#493](https://git.eeqj.de/sneak/AutistMask/issues/493)): with `showError()`
+  and `hideError()` in a fixed-height error line below the password field, as
+  the send confirmation and approval screens already did. The add wallet screen
+  showed a missing, short or mismatched password in the flash line, and the
+  private key export, recovery phrase and delete wallet screens each had a line
+  of their own above the field. On the add wallet screen the line sits beside
+  the Import button, so the button stays where it was at 360x600. Each line
+  clears when the screen is shown again and when the password is tried again.
+  The add wallet screen's other messages, such as an invalid recovery phrase, a
+  duplicate wallet and the address scan, stay in the flash line.
+  `tests/passwordErrorLines.test.js` drives all four screens in the popup.
+
+- 2026-10-07: Pre-1.0 security review of the extension
+  ([#383](https://git.eeqj.de/sneak/AutistMask/issues/383)), reading the tree at
+  `99292b9` for key handling, the DEBUG mode policy, and what the background
+  accepts from pages, the configured RPC endpoint and the explorer, with what
+  the approval screens show from it; the site permission model and storage were
+  read as well. Its summary on that issue lists ten findings, each filed as its
+  own issue, and all ten are fixed on `next`; one,
+  [#399](https://git.eeqj.de/sneak/AutistMask/issues/399), put funds at risk.
+  Three decisions it raised are still open with the owner: the Argon2id cost for
+  the vault key ([#401](https://git.eeqj.de/sneak/AutistMask/issues/401)), a
+  connected site switching the network with no prompt
+  ([#408](https://git.eeqj.de/sneak/AutistMask/issues/408)), and `eth_sign`
+  signing as a personal message
+  ([#409](https://git.eeqj.de/sneak/AutistMask/issues/409)). Not covered: the
+  end-to-end suites were not run, the bundled phishing blocklist and token list
+  were not checked entry by entry, `ethers` and `libsodium-wrappers-sumo` were
+  taken as audited, and nothing was tried against a real network with real funds
+  ([#385](https://git.eeqj.de/sneak/AutistMask/issues/385)). The planned
+  independent second check of each finding did not run; the findings rest on the
+  reviewer's own reading of the code.
+
+- 2026-10-07: Stale branches pruned from `origin`
+  ([#167](https://git.eeqj.de/sneak/AutistMask/issues/167)). The issue
+  classifies each branch it lists, with the evidence. The eighteen still on
+  `origin` that it classifies as landed, or superseded by merged pull requests,
+  were deleted. `feat/message-signing` and `fix/59-transaction-view-ui-policies`
+  had been deleted on 2026-09-09; both landed and stay deleted. Four are kept
+  because their work is not in `next`: `fix/consistent-error-display`,
+  `fix/87-consistent-error-display` and `fix/87-consistent-error-display-v2`,
+  the change for [#87](https://git.eeqj.de/sneak/AutistMask/issues/87) that
+  never landed, as reference for
+  [#493](https://git.eeqj.de/sneak/AutistMask/issues/493); and
+  `chore/token-list-enrichment`, deleted on 2026-09-09 and re-created at
+  `f7a2437`, whose `scripts/` tooling waits on
+  [#495](https://git.eeqj.de/sneak/AutistMask/issues/495).
+
+- 2026-10-07: The README says that the wallet never clears the clipboard after
+  the private key or the recovery phrase is copied, and why
+  ([#492](https://git.eeqj.de/sneak/AutistMask/issues/492)): the clipboard is
+  the user's, clearing it would go against what they expect, and it could
+  destroy something else they copied since. It is under ExportPrivKey, with a
+  line under ShowRecoveryPhrase, and names the warning each password screen
+  actually shows, which says nothing about the clipboard.
+
+- 2026-10-07: The Firefox end-to-end suite no longer tolerates any uncaught
+  extension error ([#487](https://git.eeqj.de/sneak/AutistMask/issues/487)). Its
+  one entry, Firefox reporting a popup promise that settled after the page
+  unloaded, had lost its cause with
+  [#275](https://git.eeqj.de/sneak/AutistMask/issues/275); the entry and the
+  code that printed tolerated errors are gone from `tests/e2e/firefox/run.js`,
+  and so is the README paragraph that described it.
+
+- 2026-10-07: The toolbar icons in `icons/` can be redrawn in the tree
+  ([#378](https://git.eeqj.de/sneak/AutistMask/issues/378)): `make icons` runs
+  `script/lib/icons.js`, which draws the mark and writes each PNG with node's
+  own `zlib`, no new dependency, leaving alone a file that already holds the
+  drawn image. `tests/icons.test.js` requires each committed file to hold
+  exactly that image, the same IHDR and every pixel. The compressed bytes are
+  not compared, because node's bundled zlib does not compress them as the stock
+  zlib that made the committed files did. `build.js` now copies each manifest
+  from the same path `copyIcons()` reads its icons from.
+
+- 2026-10-07: The README's end-to-end limits now match what the two browser
+  suites do to the extension
+  ([#293](https://git.eeqj.de/sneak/AutistMask/issues/293)). The `window.close`
+  override the issue named went with
+  [#275](https://git.eeqj.de/sneak/AutistMask/issues/275), so it needs no entry.
+  Added: both suites load the popup in a tab rather than from the toolbar;
+  Chrome waits 1.5 seconds before each site-connection request, records what
+  approval windows send and click, grants clipboard permission, writes text
+  straight into the page in two layout tests, and forces the leave during a
+  decrypt; Firefox forces the site-connection prompt into a window. Corrected:
+  Firefox's one tolerated error, whose cause that fix removed (the entry goes in
+  [#487](https://git.eeqj.de/sneak/AutistMask/issues/487)), the phishing
+  blocklist the extension no longer fetches, and two stale figures.
+
+- 2026-10-07: Back from Settings no longer shows Settings again after the
+  settings gear was pressed on the recovery phrase or a delete wallet screen
+  opened from Settings, with or without a reopen in between
+  ([#481](https://git.eeqj.de/sneak/AutistMask/issues/481)). Those screens take
+  themselves off the Back stack when left, which leaves Settings under Settings;
+  `goBack()` now skips an entry for the screen already showing.
+  `tests/showPhrase.test.js`, `tests/deleteWalletLostPassword.test.js` and
+  `tests/backNavigation.test.js` drive each path.
+
 - 2026-10-07: `script/discard-dist-on-failure` returns the failed step's own
   exit status even when it cannot write its message, to a closed stderr or to a
   pipe nobody reads any more
@@ -1823,6 +1947,3 @@ but the review is broader than any of them.
 
 Only work that has no issue of its own belongs here; everything else is on the
 tracker.
-
-- Cut 1.0.0 once the milestone is empty, then continue tagging as milestones
-  land.

build.js

@@ -588,15 +588,10 @@ async function build() {
         copyIcons(distDir);
     }
 
-    // copy manifests
-    copyEmitted(
-        path.join(__dirname, "manifest", "chrome.json"),
-        path.join(DIST_CHROME, "manifest.json"),
-    );
-    copyEmitted(
-        path.join(__dirname, "manifest", "firefox.json"),
-        path.join(DIST_FIREFOX, "manifest.json"),
-    );
+    // copy manifests, the same files copyIcons() read
+    for (const [distDir, manifestPath] of MANIFEST_SOURCES) {
+        copyEmitted(manifestPath, path.join(distDir, "manifest.json"));
+    }
 
     assertForbiddenTableCovered(forbiddenRecord);
 

script/lib/icons.js

@@ -0,0 +1,203 @@
+// Draws the toolbar icon and writes it to every file manifest/chrome.json
+// declares under "icons". Run by `make icons`; tests/icons.test.js checks that
+// the committed files hold exactly the image this draws.
+//
+// The icon is a dark-navy rounded square carrying a teal triangle with a
+// smaller triangle cut out of it. Every coordinate below is a fraction of the
+// icon's side, so one drawing serves every size. A pixel's colour is the
+// average of an 8x8 grid of samples, one at the centre of each cell, which
+// smooths the edges.
+//
+// The PNG is written here rather than by a library: RGBA at 8 bits per
+// channel, filter type 0 (none) on every row, one IDAT chunk compressed by
+// node's zlib at level 9. The committed files were compressed by stock zlib,
+// which node's bundled zlib does not reproduce byte for byte, so the image is
+// compared rather than the file: the IHDR and every pixel.
+
+"use strict";
+
+const fs = require("fs");
+const path = require("path");
+const zlib = require("zlib");
+
+const { icons } = require("../../manifest/chrome.json");
+
+const NAVY = [0x10, 0x1a, 0x2e];
+const TEAL = [0x35, 0xe0, 0xc2];
+const CORNER_RADIUS = 0.22;
+const OUTER_TRIANGLE = [
+    [0.5, 0.15],
+    [0.115, 0.855],
+    [0.885, 0.855],
+];
+const INNER_TRIANGLE = [
+    [0.5, 0.4],
+    [0.29, 0.7],
+    [0.71, 0.7],
+];
+const SAMPLES_PER_SIDE = 8;
+
+const PNG_SIGNATURE = Buffer.from([
+    0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a,
+]);
+
+// Points are in pixels from the icon's top-left corner.
+function insideRoundedSquare(x, y, size) {
+    const r = CORNER_RADIUS * size;
+    // How far the point is past the start of a corner's curve, on each axis.
+    const dx = Math.max(r - x, 0, x - (size - r));
+    const dy = Math.max(r - y, 0, y - (size - r));
+    return dx * dx + dy * dy <= r * r;
+}
+
+// Inside or on an edge: the point is not on opposite sides of two edges.
+function insideTriangle(x, y, [a, b, c]) {
+    const side = (p, q) =>
+        (q[0] - p[0]) * (y - p[1]) - (q[1] - p[1]) * (x - p[0]);
+    const sides = [side(a, b), side(b, c), side(c, a)];
+    return !(sides.some((s) => s < 0) && sides.some((s) => s > 0));
+}
+
+// Rounds to the nearest integer and a half to the even neighbour, as the
+// committed icons were made. Math.round takes a half up, which would change
+// some pixels by one.
+function roundHalfToEven(v) {
+    const down = Math.floor(v);
+    if (v - down !== 0.5) {
+        return Math.round(v);
+    }
+    return down % 2 === 0 ? down : down + 1;
+}
+
+// The RGBA bytes of the pixel whose top-left corner is (px, py).
+function pixel(px, py, size, outer, inner) {
+    let inSquare = 0;
+    let inTeal = 0;
+    for (let j = 0; j < SAMPLES_PER_SIDE; j++) {
+        const y = py + (j + 0.5) / SAMPLES_PER_SIDE;
+        for (let i = 0; i < SAMPLES_PER_SIDE; i++) {
+            const x = px + (i + 0.5) / SAMPLES_PER_SIDE;
+            if (!insideRoundedSquare(x, y, size)) {
+                continue;
+            }
+            inSquare++;
+            if (insideTriangle(x, y, outer) && !insideTriangle(x, y, inner)) {
+                inTeal++;
+            }
+        }
+    }
+    if (inSquare === 0) {
+        return [0, 0, 0, 0];
+    }
+    const colour = NAVY.map((navy, k) =>
+        roundHalfToEven(navy + ((TEAL[k] - navy) * inTeal) / inSquare),
+    );
+    const alpha = roundHalfToEven((255 * inSquare) / SAMPLES_PER_SIDE ** 2);
+    return [...colour, alpha];
+}
+
+// A PNG chunk: the data's length, the type, the data, then the CRC-32 of the
+// type and the data.
+function chunk(type, data) {
+    const typeAndData = Buffer.concat([Buffer.from(type, "ascii"), data]);
+    const length = Buffer.alloc(4);
+    length.writeUInt32BE(data.length);
+    const crc = Buffer.alloc(4);
+    crc.writeUInt32BE(zlib.crc32(typeAndData));
+    return Buffer.concat([length, typeAndData, crc]);
+}
+
+// The complete PNG file for the icon at `size` pixels square.
+function drawIcon(size) {
+    const toPixels = (corners) => corners.map(([x, y]) => [x * size, y * size]);
+    const outer = toPixels(OUTER_TRIANGLE);
+    const inner = toPixels(INNER_TRIANGLE);
+
+    const rows = [];
+    for (let py = 0; py < size; py++) {
+        const row = [0]; // filter type 0: the row's bytes are stored as they are
+        for (let px = 0; px < size; px++) {
+            row.push(...pixel(px, py, size, outer, inner));
+        }
+        rows.push(Buffer.from(row));
+    }
+
+    const header = Buffer.alloc(13); // compression, filter, interlace: all 0
+    header.writeUInt32BE(size, 0); // width
+    header.writeUInt32BE(size, 4); // height
+    header[8] = 8; // bits per channel
+    header[9] = 6; // colour type: RGBA
+
+    return Buffer.concat([
+        PNG_SIGNATURE,
+        chunk("IHDR", header),
+        chunk("IDAT", zlib.deflateSync(Buffer.concat(rows), { level: 9 })),
+        chunk("IEND", Buffer.alloc(0)),
+    ]);
+}
+
+// The image in a PNG: its IHDR data, and its rows after decompression, each
+// row's filter type byte first. With filter type 0 on every row, as drawIcon
+// writes, the rows are the pixels themselves; a file using another filter does
+// not match even where its pixels do. Refuses a file that is not a PNG, a chunk
+// whose CRC-32 is wrong, and any chunk but IHDR, IDAT and IEND, rather than
+// ignoring what it cannot compare.
+function decodePng(png) {
+    if (!png.subarray(0, 8).equals(PNG_SIGNATURE)) {
+        throw new Error("not a PNG");
+    }
+    let header = null;
+    const idat = [];
+    for (let pos = 8; pos < png.length; ) {
+        const length = png.readUInt32BE(pos);
+        const typeAndData = png.subarray(pos + 4, pos + 8 + length);
+        const type = typeAndData.toString("ascii", 0, 4);
+        if (zlib.crc32(typeAndData) !== png.readUInt32BE(pos + 8 + length)) {
+            throw new Error(`the ${type} chunk fails its CRC-32`);
+        }
+        if (type === "IHDR") {
+            header = typeAndData.subarray(4);
+        } else if (type === "IDAT") {
+            idat.push(typeAndData.subarray(4));
+        } else if (type !== "IEND") {
+            throw new Error(`unexpected ${type} chunk`);
+        }
+        pos += 12 + length;
+    }
+    if (header === null) {
+        throw new Error("no IHDR chunk");
+    }
+    return { header, rows: zlib.inflateSync(Buffer.concat(idat)) };
+}
+
+// True when `file` already holds the image in `png`. A file that is missing or
+// cannot be read as a PNG does not, and is written over.
+function holdsSameImage(file, png) {
+    let existing;
+    try {
+        existing = decodePng(fs.readFileSync(file));
+    } catch {
+        return false;
+    }
+    const drawn = decodePng(png);
+    return (
+        existing.header.equals(drawn.header) && existing.rows.equals(drawn.rows)
+    );
+}
+
+// A file already holding the drawn image is left alone, so running this does
+// not rewrite the committed icons with node's compression.
+if (require.main === module) {
+    for (const [size, file] of Object.entries(icons)) {
+        const target = path.join(__dirname, "..", "..", file);
+        const png = drawIcon(Number(size));
+        if (holdsSameImage(target, png)) {
+            console.log(`icons: ${file} already holds this image`);
+            continue;
+        }
+        fs.writeFileSync(target, png);
+        console.log(`icons: wrote ${file}`);
+    }
+}
+
+module.exports = { drawIcon, decodePng };

src/background/index.js

@@ -137,11 +137,12 @@ function releaseTxApprovalSlotFor(approvalId) {
     }
 }
 
-// One site-connection approval and one sign approval per site at a time: a
-// page that asks again before the user has answered is refused with the code
-// above instead of opening another window, so it cannot bury the user in
-// prompts. The pending approval itself holds the place, so a caller must test
-// this and raise its approval with nothing awaited in between.
+// One site-connection approval, one sign approval and one network-switch
+// approval per site at a time: a page that asks again before the user has
+// answered is refused with the code above instead of opening another window,
+// so it cannot bury the user in prompts. The pending approval itself holds the
+// place, so a caller must test this and raise its approval with nothing awaited
+// in between.
 function findPendingApproval(origin, type) {
     return Object.values(pendingApprovals).find(
         (approval) => approval.origin === origin && approval.type === type,
@@ -348,8 +349,9 @@ function settleApproval(id, result, options) {
 
 // What a pending approval resolves to when it is given up on rather than
 // answered: the window was closed, or could not be opened at all. A tx or sign
-// approval answers the requesting page in EIP-1193 shape; a site-connection
-// approval answers the connection handler in its own.
+// approval answers the requesting page in EIP-1193 shape; a site-connection or
+// network-switch approval answers its handler in the shape the popup's
+// decision has, as a refusal.
 function abandonedResult(approval, code, message) {
     if (approval.type === "tx" || approval.type === "sign") {
         return { error: { code, message } };
@@ -588,6 +590,26 @@ function requestSignApproval(origin, signParams, approvedFrom) {
     });
 }
 
+// Open a network-switch approval popup and return a promise that resolves with
+// { approved }. Opened in a window, as tx and sign approvals are, because a
+// site's request is not a user gesture. The popup answers on the approval port,
+// as a site-connection approval does.
+function requestNetworkApproval(origin, currentNetworkId, requestedNetworkId) {
+    return new Promise((resolve) => {
+        const id = crypto.randomUUID();
+        pendingApprovals[id] = {
+            id,
+            origin,
+            currentNetworkId,
+            requestedNetworkId,
+            resolve,
+            type: "network",
+        };
+
+        openApprovalWindow(id);
+    });
+}
+
 // Anything only the extension's own pages may say. A content script speaks
 // with the page's URL, so this is what separates the popup from the site the
 // popup is being asked about.
@@ -597,8 +619,8 @@ function isExtensionSender(sender) {
 }
 
 // The approval popup's port: it carries the user's decision on a
-// site-connection approval, and its disconnect is how that approval learns the
-// popup closed without one.
+// site-connection or network-switch approval, and its disconnect is how that
+// approval learns the popup closed without one.
 //
 // The decision travels this port rather than a one-off runtime.sendMessage()
 // for exactly one reason: the port is also what the popup's window.close()
@@ -806,6 +828,10 @@ async function handleRpc(method, params, origin) {
         // tab is served from, so a page the user never connected to must
         // not be able to do it. Ungated, any page could clear the
         // [TESTNET] banner under a user who believed they were on Sepolia.
+        //
+        // A connected site does not switch it either: only the user does,
+        // by approving the request on the prompt below
+        // (https://git.eeqj.de/sneak/AutistMask/issues/408).
         const s = await getState();
         const activeAddress = activeAddressOf(s);
         const allowed = s.allowedSites[activeAddress] || [];
@@ -827,6 +853,27 @@ async function handleRpc(method, params, origin) {
         }
         if (SUPPORTED_CHAIN_IDS.has(chainId)) {
             const target = networkByChainId(chainId);
+            if (findPendingApproval(origin, "network")) {
+                return {
+                    error: {
+                        code: APPROVAL_PENDING_CODE,
+                        message: APPROVAL_PENDING_MESSAGE,
+                    },
+                };
+            }
+            const decision = await requestNetworkApproval(
+                origin,
+                s.networkId,
+                target.id,
+            );
+            if (!decision.approved) {
+                return {
+                    error: {
+                        code: APPROVAL_REJECTED_CODE,
+                        message: APPROVAL_REJECTED_MESSAGE,
+                    },
+                };
+            }
             // Read-modify-write against storage. The old path went through
             // onChainSwitch(), which mutates the singleton and then persists
             // every field of it — on an unloaded worker that wrote empty
@@ -1345,20 +1392,21 @@ startBackgroundJobs();
 // which then fails retryably settles instead of waiting in a window that no
 // longer exists.
 //
-// A site-connection approval whose popup connected its port is not decided
-// here. That popup approves and closes in the same breath, and this event
-// races the decision on a channel of its own — the same race the port exists
-// to end. Its port disconnect says the same thing this event does, in an order
-// that is defined, so the disconnect is left to say it. The window closing
-// before any port connected is the one case with nothing else to speak for it,
-// and is rejected here so the dApp is not left waiting on a window that is
-// gone.
+// A site-connection or network-switch approval whose popup connected its port
+// is not decided here. That popup approves and closes in the same breath, and
+// this event races the decision on a channel of its own — the same race the
+// port exists to end. Its port disconnect says the same thing this event does,
+// in an order that is defined, so the disconnect is left to say it. The window
+// closing before any port connected is the one case with nothing else to speak
+// for it, and is rejected here so the dApp is not left waiting on a window that
+// is gone.
 if (windowsNs && windowsNs.onRemoved) {
     windowsNs.onRemoved.addListener((windowId) => {
         for (const [id, approval] of Object.entries(pendingApprovals)) {
             if (approval.windowId !== windowId) continue;
-            const isSite = approval.type !== "tx" && approval.type !== "sign";
-            if (isSite && approval.portConnected) continue;
+            const decidedOnPort =
+                approval.type !== "tx" && approval.type !== "sign";
+            if (decidedOnPort && approval.portConnected) continue;
             const rejection = abandonedResult(
                 approval,
                 APPROVAL_REJECTED_CODE,
@@ -1446,6 +1494,11 @@ runtime.onMessage.addListener((msg, sender, sendResponse) => {
                 resp.signParams = approval.signParams;
                 resp.approvedFrom = approval.approvedFrom;
             }
+            if (approval.type === "network") {
+                resp.type = "network";
+                resp.currentNetworkId = approval.currentNetworkId;
+                resp.requestedNetworkId = approval.requestedNetworkId;
+            }
             // Flag if the requesting domain is on the phishing blocklist.
             resp.isPhishingDomain = isPhishingDomain(
                 extractHostname(approval.origin),

src/popup/index.html

@@ -207,12 +207,22 @@
                         class="border border-border p-1 w-full font-mono text-sm bg-bg text-fg"
                     />
                 </div>
-                <button
-                    id="btn-add-wallet-confirm"
-                    class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
-                >
-                    Import
-                </button>
+                <!-- The error line sits beside Import, not above it: at
+                     360x600 the button already starts near the bottom of
+                     the popup, and a line of its own would push it below
+                     the fold. The longest error fits on one line here. -->
+                <div class="flex items-center gap-2">
+                    <button
+                        id="btn-add-wallet-confirm"
+                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
+                    >
+                        Import
+                    </button>
+                    <div
+                        id="add-wallet-password-error"
+                        class="text-xs min-h-[1.25rem] invisible"
+                    ></div>
+                </div>
             </div>
 
             <!-- ============ MAIN VIEW: ALL WALLETS & ADDRESSES ============ -->
@@ -396,10 +406,6 @@
                     Warning: anyone with this private key can access and
                     transfer all funds from this address. Never share it.
                 </p>
-                <div
-                    id="export-privkey-flash"
-                    class="text-xs mb-2 min-h-[1.25rem] invisible"
-                ></div>
                 <div id="export-privkey-password-section" class="mb-2">
                     <label class="block mb-1">Password</label>
                     <input
@@ -408,9 +414,13 @@
                         class="border border-border p-1 w-full font-mono text-sm bg-bg text-fg"
                         placeholder="Enter your password to continue"
                     />
+                    <div
+                        id="export-privkey-password-error"
+                        class="text-xs mt-2 mb-2 min-h-[1.25rem] invisible"
+                    ></div>
                     <button
                         id="btn-export-privkey-confirm"
-                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer mt-2"
+                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
                     >
                         Reveal
                     </button>
@@ -1116,10 +1126,6 @@
                     <strong id="delete-wallet-name"></strong> is permanent. Any
                     funds will be unrecoverable without your recovery phrase.
                 </p>
-                <div
-                    id="delete-wallet-flash"
-                    class="text-xs text-red-500 mb-2 min-h-[1.25rem] invisible"
-                ></div>
                 <div class="mb-2">
                     <label class="block mb-1">Password</label>
                     <input
@@ -1129,6 +1135,10 @@
                         placeholder="Enter your password to confirm"
                     />
                 </div>
+                <div
+                    id="delete-wallet-password-error"
+                    class="text-xs mb-2 min-h-[1.25rem] invisible"
+                ></div>
                 <button
                     id="btn-delete-wallet-confirm"
                     class="border border-border text-red-500 px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
@@ -1273,10 +1283,6 @@
                     this wallet, from any device, without your password. Never
                     type them into a website and never show them to anyone.
                 </div>
-                <div
-                    id="show-phrase-flash"
-                    class="text-xs text-red-500 mb-2 min-h-[1.25rem] invisible"
-                ></div>
                 <div id="show-phrase-password-section" class="mb-2">
                     <label class="block mb-1">Password</label>
                     <input
@@ -1285,9 +1291,13 @@
                         class="border border-border p-1 w-full font-mono text-sm bg-bg text-fg"
                         placeholder="Enter your password to continue"
                     />
+                    <div
+                        id="show-phrase-password-error"
+                        class="text-xs mt-2 mb-2 min-h-[1.25rem] invisible"
+                    ></div>
                     <button
                         id="btn-show-phrase-reveal"
-                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer mt-2"
+                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
                     >
                         Reveal
                     </button>
@@ -1731,6 +1741,54 @@
                 </div>
             </div>
 
+            <!-- ============ NETWORK SWITCH APPROVAL ============ -->
+            <div id="view-approve-network" class="view hidden">
+                <h2 class="font-bold mb-2">Network Switch Request</h2>
+                <div
+                    id="approve-network-phishing-warning"
+                    class="mb-3 p-2 text-xs font-bold hidden bg-red-100 text-red-800 border-2 border-red-600 rounded-md"
+                >
+                    ⚠️ PHISHING WARNING: This site is on a known phishing
+                    blocklist. Proceed with extreme caution.
+                </div>
+                <p class="mb-2">
+                    <span id="approve-network-origin" class="font-bold"></span>
+                    wants to switch the wallet's network.
+                </p>
+                <div class="mb-3">
+                    <div class="text-xs text-muted mb-1">Current network</div>
+                    <div
+                        id="approve-network-current"
+                        class="text-xs font-bold"
+                    ></div>
+                </div>
+                <div class="mb-3">
+                    <div class="text-xs text-muted mb-1">Requested network</div>
+                    <div
+                        id="approve-network-requested"
+                        class="text-xs font-bold"
+                    ></div>
+                </div>
+                <p class="mb-3 text-xs">
+                    Switching changes the network for the whole wallet and for
+                    every site, not only for this one.
+                </p>
+                <div class="flex justify-between">
+                    <button
+                        id="btn-approve-network"
+                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
+                    >
+                        Switch
+                    </button>
+                    <button
+                        id="btn-reject-network"
+                        class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer"
+                    >
+                        Reject
+                    </button>
+                </div>
+            </div>
+
             <!-- ============ STATE RECOVERY ============ -->
             <!--
                 Shown when the stored profile cannot be read at all. Every

src/popup/index.js

@@ -238,9 +238,9 @@ async function init() {
         // rejection rather than an uncaught error — measured as still failing
         // the run on both harnesses (Playwright `pageerror`, and the Firefox
         // driver's console-service drain), so nothing is lost by leaving it
-        // on that path.
+        // on that path. show() puts the approval's own screen up once the
+        // background has described it.
         approval.show(approvalId);
-        showView("approve-site");
         return;
     }
 

src/popup/views/addWallet.js

@@ -2,6 +2,8 @@ const {
     $,
     showView,
     showFlash,
+    showError,
+    hideError,
     goBack,
     clearViewStack,
     onViewLeave,
@@ -98,6 +100,7 @@ function clear() {
     $("add-wallet-password").value = "";
     $("add-wallet-password-confirm").value = "";
     $("add-wallet-phrase-warning").style.visibility = "hidden";
+    hideError("add-wallet-password-error");
 }
 
 // Each wallet has its own password (its own encryptedSecret), so adding a
@@ -125,15 +128,18 @@ function validatePassword() {
     const pw = $("add-wallet-password").value;
     const pw2 = $("add-wallet-password-confirm").value;
     if (!pw) {
-        showFlash("Please choose a password.");
+        showError("add-wallet-password-error", "Please choose a password.");
         return null;
     }
     if (pw.length < 12) {
-        showFlash("Password must be at least 12 characters.");
+        showError(
+            "add-wallet-password-error",
+            "Password must be at least 12 characters.",
+        );
         return null;
     }
     if (pw !== pw2) {
-        showFlash("Passwords do not match.");
+        showError("add-wallet-password-error", "Passwords do not match.");
         return null;
     }
     return pw;
@@ -342,8 +348,10 @@ function init(ctx) {
         $("add-wallet-phrase-warning").style.visibility = "visible";
     });
 
-    // Import / confirm
+    // Import / confirm. Each press starts with no password error on screen:
+    // validatePassword() puts it back if the password is still wrong.
     $("btn-add-wallet-confirm").addEventListener("click", async () => {
+        hideError("add-wallet-password-error");
         if (currentMode === "mnemonic") {
             await importMnemonic(ctx);
         } else if (currentMode === "privkey") {

src/popup/views/approval.js

@@ -14,6 +14,7 @@ const {
 } = require("./helpers");
 const { state, saveState } = require("../../shared/state");
 const {
+    networkById,
     networkByChainId,
     nativeCurrencyByChainId,
 } = require("../../shared/networks");
@@ -752,9 +753,29 @@ function showSignApproval(details) {
     );
 }
 
+function showNetworkApproval(details) {
+    showPhishingWarning(
+        "approve-network-phishing-warning",
+        details.isPhishingDomain,
+    );
+    $("approve-network-origin").textContent = details.origin;
+    $("approve-network-current").textContent = networkById(
+        details.currentNetworkId,
+    ).name;
+    $("approve-network-requested").textContent = networkById(
+        details.requestedNetworkId,
+    ).name;
+    showView("approve-network");
+}
+
 // Awaited by nobody: the popup entry point calls this and moves on. It
 // therefore has to absorb its own failure, and a background that cannot
 // describe the approval is the same outcome as an approval that is gone.
+//
+// Nothing is on screen until the background has described the approval, so
+// the screen shown is always the one for the approval this window answers:
+// the connection prompt's "Allow" and the network switch prompt's "Switch"
+// answer on the same port, and either would approve the other.
 async function show(id) {
     approvalId = id;
     approvalPort = runtimeApi().connect({ name: "approval:" + id });
@@ -778,6 +799,10 @@ async function show(id) {
         showSignApproval(details);
         return;
     }
+    if (details.type === "network") {
+        showNetworkApproval(details);
+        return;
+    }
     // Site connection approval
     showPhishingWarning(
         "approve-site-phishing-warning",
@@ -787,6 +812,7 @@ async function show(id) {
     $("approve-address").innerHTML = approvalAddressHtml(state.activeAddress);
     attachCopyHandlers("view-approve-site");
     $("approve-remember").checked = state.rememberSiteChoice;
+    showView("approve-site");
 }
 
 let approvalId = null;
@@ -866,20 +892,21 @@ function clearSignPassword() {
     hideError("approve-sign-error");
 }
 
-// Answer a site-connection approval and close. The decision goes out on the
-// approval port — see approvalPort above for why — and carries no approval id,
-// because the port name already names the approval the background will settle.
-// The post is guarded because a throw must not cost the close: posting on a
-// port whose background worker has been torn down throws, and the approval it
-// would have settled died with that worker, so the only thing left to do is
-// what the user asked for — go away.
-function decideSite(approved) {
+// Answer a site-connection or network-switch approval and close. The decision
+// goes out on the approval port — see approvalPort above for why — and carries
+// no approval id, because the port name already names the approval the
+// background will settle. `remember` means something only for a site
+// connection. The post is guarded because a throw must not cost the close:
+// posting on a port whose background worker has been torn down throws, and the
+// approval it would have settled died with that worker, so the only thing left
+// to do is what the user asked for — go away.
+function decide(approved, remember) {
     if (approvalPort) {
         try {
             approvalPort.postMessage({
                 type: "AUTISTMASK_APPROVAL_DECISION",
                 approved,
-                remember: $("approve-remember").checked,
+                remember,
             });
         } catch {
             // Nothing to report it to; the window closes either way.
@@ -898,11 +925,19 @@ function init(_ctx) {
     });
 
     $("btn-approve").addEventListener("click", () => {
-        decideSite(true);
+        decide(true, $("approve-remember").checked);
     });
 
     $("btn-reject").addEventListener("click", () => {
-        decideSite(false);
+        decide(false, $("approve-remember").checked);
+    });
+
+    $("btn-approve-network").addEventListener("click", () => {
+        decide(true, false);
+    });
+
+    $("btn-reject-network").addEventListener("click", () => {
+        decide(false, false);
     });
 
     $("btn-approve-tx").addEventListener("click", async () => {

src/popup/views/deleteWallet.js

@@ -2,6 +2,8 @@ const {
     $,
     showView,
     showFlash,
+    showError,
+    hideError,
     goBack,
     clearViewStack,
     onViewLeave,
@@ -55,8 +57,7 @@ function confirmKey(name) {
 function clear() {
     deleteWalletIndex = null;
     $("delete-wallet-password").value = "";
-    $("delete-wallet-flash").textContent = "";
-    $("delete-wallet-flash").style.visibility = "hidden";
+    hideError("delete-wallet-password-error");
 }
 
 // The lost-password screen holds no secret — a wallet name is not one —
@@ -232,19 +233,22 @@ function init(_ctx) {
     $("btn-delete-wallet-confirm").addEventListener("click", async () => {
         const pw = $("delete-wallet-password").value;
         if (!pw) {
-            $("delete-wallet-flash").textContent =
-                "Please enter your password.";
-            $("delete-wallet-flash").style.visibility = "visible";
+            showError(
+                "delete-wallet-password-error",
+                "Please enter your password.",
+            );
             return;
         }
 
         if (deleteWalletIndex === null) {
-            $("delete-wallet-flash").textContent =
-                "No wallet selected for deletion.";
-            $("delete-wallet-flash").style.visibility = "visible";
+            showError(
+                "delete-wallet-password-error",
+                "No wallet selected for deletion.",
+            );
             return;
         }
 
+        hideError("delete-wallet-password-error");
         const btn = $("btn-delete-wallet-confirm");
         btn.disabled = true;
         btn.classList.add("text-muted");
@@ -256,9 +260,10 @@ function init(_ctx) {
         try {
             await decryptWithPassword(wallet.encryptedSecret, pw);
         } catch {
-            $("delete-wallet-flash").textContent =
-                "That password is incorrect. Please try again.";
-            $("delete-wallet-flash").style.visibility = "visible";
+            showError(
+                "delete-wallet-password-error",
+                "That password is incorrect. Please try again.",
+            );
             btn.disabled = false;
             btn.classList.remove("text-muted");
             return;

src/popup/views/exportPrivkey.js

@@ -20,6 +20,8 @@ const {
     $,
     showView,
     showFlash,
+    showError,
+    hideError,
     flashCopyFeedback,
     goBack,
     onViewLeave,
@@ -56,11 +58,6 @@ function isCurrentReveal(generation) {
     );
 }
 
-function fail(message) {
-    $("export-privkey-flash").textContent = message;
-    $("export-privkey-flash").style.visibility = "visible";
-}
-
 // Wipe every trace of the key and drop the address selection. Safe to call
 // when nothing was ever revealed, and safe to call twice.
 function clear() {
@@ -71,8 +68,7 @@ function clear() {
     $("export-privkey-password").value = "";
     $("export-privkey-result").classList.add("hidden");
     $("export-privkey-password-section").classList.remove("hidden");
-    $("export-privkey-flash").textContent = "";
-    $("export-privkey-flash").style.visibility = "hidden";
+    hideError("export-privkey-password-error");
 }
 
 function show(walletIdx, addrIdx) {
@@ -112,15 +108,19 @@ function show(walletIdx, addrIdx) {
 async function reveal() {
     const password = $("export-privkey-password").value;
     if (!password) {
-        fail("Please enter your password.");
+        showError(
+            "export-privkey-password-error",
+            "Please enter your password.",
+        );
         return;
     }
     if (walletIndex === null) {
-        fail("No address is selected.");
+        showError("export-privkey-password-error", "No address is selected.");
         return;
     }
     const wallet = state.wallets[walletIndex];
 
+    hideError("export-privkey-password-error");
     const btn = $("btn-export-privkey-confirm");
     btn.disabled = true;
     btn.classList.add("text-muted");
@@ -140,11 +140,12 @@ async function reveal() {
         $("export-privkey-password-section").classList.add("hidden");
         $("export-privkey-value").textContent = signer.privateKey;
         $("export-privkey-result").classList.remove("hidden");
-        $("export-privkey-flash").textContent = "";
-        $("export-privkey-flash").style.visibility = "hidden";
     } catch {
         if (!isCurrentReveal(generation)) return;
-        fail("That password is incorrect. Please try again.");
+        showError(
+            "export-privkey-password-error",
+            "That password is incorrect. Please try again.",
+        );
     } finally {
         btn.disabled = false;
         btn.classList.remove("text-muted");

src/popup/views/helpers.js

@@ -51,6 +51,7 @@ const VIEWS = [
     "approve-site",
     "approve-tx",
     "approve-sign",
+    "approve-network",
     "export-privkey",
     "show-phrase",
     // Shown by src/popup/views/stateRecovery.js when the stored profile
@@ -216,10 +217,21 @@ function pushCurrentView() {
 
 // Pop the navigation stack and show the previous view.  If the stack
 // is empty, fall back to the main (home) view.
+//
+// An entry for the view already showing is skipped: landing on it would
+// make Back seem to do nothing. Settings, the recovery phrase or delete
+// wallet screen, then the gear leaves Settings under Settings, because that
+// screen takes itself off the stack when left, and a reopened popup cuts it
+// off the restored stack the same way
+// (https://git.eeqj.de/sneak/AutistMask/issues/481).
 function goBack() {
+    const stack = state.viewStack;
+    while (stack.length > 0 && stack[stack.length - 1] === state.currentView) {
+        stack.pop();
+    }
     let target;
-    if (state.viewStack.length > 0) {
-        target = state.viewStack.pop();
+    if (stack.length > 0) {
+        target = stack.pop();
     } else {
         target = "main";
     }

src/popup/views/showPhrase.js

@@ -21,6 +21,8 @@ const {
     $,
     showView,
     showFlash,
+    showError,
+    hideError,
     flashCopyFeedback,
     goBack,
     onViewLeave,
@@ -52,11 +54,6 @@ function isCurrentReveal(generation) {
     );
 }
 
-function fail(message) {
-    $("show-phrase-flash").textContent = message;
-    $("show-phrase-flash").style.visibility = "visible";
-}
-
 // Wipe every trace of the phrase and drop the wallet selection. Safe to
 // call when nothing was ever revealed, and safe to call twice.
 function clear() {
@@ -66,8 +63,7 @@ function clear() {
     $("show-phrase-password").value = "";
     $("show-phrase-result").classList.add("hidden");
     $("show-phrase-password-section").classList.remove("hidden");
-    $("show-phrase-flash").textContent = "";
-    $("show-phrase-flash").style.visibility = "hidden";
+    hideError("show-phrase-password-error");
 }
 
 function show(walletIdx) {
@@ -90,19 +86,23 @@ function show(walletIdx) {
 async function reveal() {
     const password = $("show-phrase-password").value;
     if (!password) {
-        fail("Please enter your password.");
+        showError("show-phrase-password-error", "Please enter your password.");
         return;
     }
     if (walletIndex === null) {
-        fail("No wallet is selected.");
+        showError("show-phrase-password-error", "No wallet is selected.");
         return;
     }
     const wallet = state.wallets[walletIndex];
     if (!walletHasRecoveryPhrase(wallet)) {
-        fail("This wallet does not have a recovery phrase.");
+        showError(
+            "show-phrase-password-error",
+            "This wallet does not have a recovery phrase.",
+        );
         return;
     }
 
+    hideError("show-phrase-password-error");
     const btn = $("btn-show-phrase-reveal");
     btn.disabled = true;
     btn.classList.add("text-muted");
@@ -120,13 +120,14 @@ async function reveal() {
         $("show-phrase-password-section").classList.add("hidden");
         $("show-phrase-value").textContent = phrase;
         $("show-phrase-result").classList.remove("hidden");
-        $("show-phrase-flash").textContent = "";
-        $("show-phrase-flash").style.visibility = "hidden";
     } catch {
         if (!isCurrentReveal(generation)) return;
         // Deliberately not the caught error: the message is fixed so that
         // nothing derived from the ciphertext or the attempt can surface.
-        fail("That password is incorrect. Please try again.");
+        showError(
+            "show-phrase-password-error",
+            "That password is incorrect. Please try again.",
+        );
     } finally {
         btn.disabled = false;
         btn.classList.remove("text-muted");

tests/addressScanCancelled.test.js

@@ -39,6 +39,8 @@ jest.doMock("../src/popup/views/helpers", () => ({
     $: element,
     showView: () => {},
     showFlash: () => {},
+    showError: () => {},
+    hideError: () => {},
     goBack: () => {},
     clearViewStack: () => {},
     onViewLeave: () => {},

tests/approvalOrigin.test.js

@@ -1,5 +1,5 @@
-// The connection, transaction and signature prompts name the site by its full
-// origin, scheme and port included, not by its bare hostname
+// The connection, transaction, signature and network switch prompts name the
+// site by its full origin, scheme and port included, not by its bare hostname
 // (https://git.eeqj.de/sneak/AutistMask/issues/402). A page served over http,
 // or on another port, of a host the user trusts over https must not raise a
 // prompt that reads as that trusted site.
@@ -104,6 +104,7 @@ beforeEach(() => {
 test("the connection prompt shows the origin", async () => {
     await openApproval({});
     expect(node("approve-origin").textContent).toBe(ORIGIN);
+    expect(node("view-approve-site").classList.contains("hidden")).toBe(false);
 });
 
 test("the transaction prompt shows the origin", async () => {
@@ -138,3 +139,24 @@ test("the signature prompt shows the origin", async () => {
     });
     expect(node("approve-sign-origin").textContent).toBe(ORIGIN);
 });
+
+test("the network switch prompt shows the origin and both networks", async () => {
+    await openApproval({
+        type: "network",
+        currentNetworkId: "mainnet",
+        requestedNetworkId: "sepolia",
+    });
+    expect(node("approve-network-origin").textContent).toBe(ORIGIN);
+    expect(node("approve-network-current").textContent).toBe(
+        "Ethereum Mainnet",
+    );
+    expect(node("approve-network-requested").textContent).toBe(
+        "Sepolia Testnet",
+    );
+    // Its own screen, and not the connection prompt, whose "Allow" answers
+    // on the same port.
+    expect(node("view-approve-network").classList.contains("hidden")).toBe(
+        false,
+    );
+    expect(node("view-approve-site").classList.contains("hidden")).toBe(true);
+});

tests/backNavigation.test.js

@@ -52,6 +52,7 @@ const {
     resetRenderedViews,
 } = require("../src/popup/viewRouter");
 const { state } = require("../src/shared/state");
+const { restorableStack } = require("../src/shared/persistedState");
 
 const ADDRESS = "0x1111111111111111111111111111111111111111";
 const TOKEN = "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48";
@@ -209,6 +210,23 @@ describe("Back onto a view the reopened popup never rendered", () => {
     });
 });
 
+// https://git.eeqj.de/sneak/AutistMask/issues/481. Settings, the recovery
+// phrase or delete wallet screen, the gear, then a reopen: the restored stack
+// is cut at the screen the gear left, which leaves Settings under the Settings
+// the popup reopens onto.
+describe("Back from Settings reopened over its own entry", () => {
+    test.each(["show-phrase", "delete-wallet-confirm"])(
+        "goes to the screen under it after leaving %s",
+        (left) => {
+            const stored = ["main", "settings", left];
+            reopenedOn("settings", restorableStack(stored, "settings"));
+            goBack();
+            expect(calls).toEqual(["main"]);
+            expect(state.currentView).toBe("main");
+        },
+    );
+});
+
 // The guards are restoreView()'s, so a popped view whose backing data is
 // gone lands on Home rather than on an empty template.
 describe("Back onto a view whose backing data is gone", () => {

tests/backgroundStateIsolation.test.js

@@ -25,6 +25,7 @@
 
 const { Wallet } = require("ethers");
 const { networkById } = require("../src/shared/networks");
+const { applyChainSwitchFields } = require("../src/shared/chainSwitchFields");
 const { makeStorageStub } = require("./support/storageStub");
 
 const SIGNER_KEY =
@@ -240,8 +241,8 @@ describe("a chain switch under a transaction already committed to a chain", () =
     // The artifact is verified against the chain read at the top of the
     // attempt. Whatever endpoint it is then broadcast to has to be that same
     // chain's — otherwise the wallet checks a transaction against Sepolia and
-    // sends it to a mainnet node. A connected site can switch the chain at any
-    // moment, including this one.
+    // sends it to a mainnet node. The user can switch the network in Settings
+    // at any moment, including this one.
     test("the artifact is broadcast to the endpoint of the chain it was verified against", async () => {
         const bg = loadWorker("sepolia");
 
@@ -264,9 +265,9 @@ describe("a chain switch under a transaction already committed to a chain", () =
             populated(Number(SEPOLIA.networkVersion)),
         );
 
-        // A connected site switches the chain while the attempt is running,
-        // and the switch is committed to storage in full before the attempt
-        // goes any further.
+        // The user switches the network in Settings while the attempt is
+        // running: the popup writes the switched record to storage in full
+        // before the attempt goes any further.
         //
         // It is fired from inside the attempt's SECOND state read, because
         // that is where the window used to be: the chain id was captured at
@@ -277,18 +278,18 @@ describe("a chain switch under a transaction already committed to a chain", () =
         // this to fire on, and the switch below runs after the attempt is
         // done instead — which is the point.
         let reads = 0;
-        let switched = null;
-        const doSwitch = async () => {
-            switched = bg.rpc("wallet_switchEthereumChain", [
-                { chainId: MAINNET.chainId },
-            ]);
-            await settle();
+        let switched = false;
+        const doSwitch = () => {
+            const record = bg.persisted();
+            applyChainSwitchFields(record, MAINNET.id);
+            global.chrome.storage.write("autistmask", record);
+            switched = true;
         };
         bg.setGetHook(async () => {
             reads++;
             if (reads !== 2) return;
             bg.setGetHook(null);
-            await doSwitch();
+            doSwitch();
         });
 
         const attempt = bg.send(
@@ -303,8 +304,7 @@ describe("a chain switch under a transaction already committed to a chain", () =
         await settle();
 
         bg.setGetHook(null);
-        if (!switched) await doSwitch();
-        expect(switched.result()).toEqual({ result: null });
+        if (!switched) doSwitch();
         expect(bg.persisted().networkId).toBe("mainnet");
         await settle();
 

tests/chainSwitchGate.test.js

@@ -1,16 +1,22 @@
-// Who may move the active chain.
+// Who may move the active chain, and when.
 //
 // wallet_switchEthereumChain used to be answered for any origin at all, with
 // no connection check and no prompt, so a page the user had never connected
 // to could clear the [TESTNET] banner under someone who believed they were
-// on Sepolia (https://git.eeqj.de/sneak/AutistMask/issues/308). The refusal
-// is asserted as a refusal to ACT — the state unmoved and no chainChanged
-// broadcast — because an error code alone would not distinguish a gate from
-// a switch that happened and then reported a failure.
+// on Sepolia (https://git.eeqj.de/sneak/AutistMask/issues/308). Gated on the
+// connection, a connected site could still move the wallet between mainnet and
+// Sepolia without asking. Only the user switches the network: a connected
+// site's request opens a prompt, and nothing changes unless the user approves
+// it there (https://git.eeqj.de/sneak/AutistMask/issues/408).
 //
-// The endpoint half of that issue lives in tests/networkEndpoints.test.js,
-// which covers the popup's chain switch; this file covers the background's,
-// which goes through storage rather than the shared state singleton.
+// Every refusal is asserted as a refusal to ACT — the stored record unmoved
+// and no chainChanged broadcast — because an error code alone would not
+// distinguish a refusal from a switch that happened and then reported a
+// failure.
+//
+// The endpoint half of #308 lives in tests/networkEndpoints.test.js, which
+// covers the popup's chain switch; this file covers the background's, which
+// goes through storage rather than the shared state singleton.
 
 const { networkById } = require("../src/shared/networks");
 const { makeStorageStub } = require("./support/storageStub");
@@ -21,18 +27,23 @@ const ADDRESS = "0x66133E8ea0f5D1d612D2502a968757D1048c214a";
 const CONNECTED_ORIGIN = "https://dapp.example";
 const STRANGER_ORIGIN = "https://stranger.example";
 
+const EXT_URL = "chrome-extension://autistmask/";
+
 const MAINNET = networkById("mainnet");
 const SEPOLIA = networkById("sepolia");
 
 // The user's own node, so a switch that happens is visible as the loss of it.
 const CUSTOM_RPC = "http://127.0.0.1:8545";
 
+// A balance a switch would clear, so a switch that happens is visible here too.
 function walletFixture() {
     return [
         {
             name: "Wallet 1",
             type: "hd",
-            addresses: [{ address: ADDRESS, balance: "0", tokenBalances: [] }],
+            addresses: [
+                { address: ADDRESS, balance: "1.5", tokenBalances: [] },
+            ],
         },
     ];
 }
@@ -47,10 +58,6 @@ afterEach(() => {
     delete global.chrome;
 });
 
-// ---------------------------------------------------------------------------
-// The gate: which origins the background will switch the chain for.
-// ---------------------------------------------------------------------------
-
 // Load the background worker against stubbed browser APIs, with the real
 // chain-switch and persistence modules behind it, and return the handles to
 // drive it.
@@ -91,30 +98,46 @@ function loadBackground() {
     const storage = makeStorageStub({ autistmask: persisted });
 
     let messageListener = null;
+    let connectListener = null;
+    let windowRemovedListener = null;
+    // The URL of every approval window the background opened. The approval id
+    // is in it, and that is how the popup learns which approval it answers.
+    const opened = [];
     // Every message the background pushed at a content script. chainChanged
-    // is what tells a page the wallet moved, so an ungated switch is visible
-    // here as well as in the state.
+    // is what tells a page the wallet moved, so a switch is visible here as
+    // well as in the state.
     const toTabs = [];
 
     global.chrome = {
         storage,
         runtime: {
-            getURL: (path) => "chrome-extension://autistmask/" + path,
+            getURL: (path) => EXT_URL + path,
             onMessage: {
                 addListener: (fn) => {
                     messageListener = fn;
                 },
             },
-            onConnect: { addListener: () => {} },
+            onConnect: {
+                addListener: (fn) => {
+                    connectListener = fn;
+                },
+            },
             lastError: null,
         },
         windows: {
             getLastFocused: (cb) => cb(null),
-            create: (options, cb) => cb({ id: 1 }),
+            create: (options, cb) => {
+                opened.push(options.url);
+                cb({ id: opened.length });
+            },
             remove: (id, cb) => {
                 if (cb) cb();
             },
-            onRemoved: { addListener: () => {} },
+            onRemoved: {
+                addListener: (fn) => {
+                    windowRemovedListener = fn;
+                },
+            },
         },
         tabs: {
             query: (queryInfo, cb) => cb([{ id: 1 }]),
@@ -128,6 +151,8 @@ function loadBackground() {
 
     require("../src/background/index");
 
+    // A page's request. Its answer is read with result(), which is null for as
+    // long as the request is waiting on the user.
     async function switchChain(chainId, origin) {
         let result = null;
         messageListener(
@@ -142,56 +167,147 @@ function loadBackground() {
             },
         );
         await settle();
-        return result;
+        return { result: () => result };
+    }
+
+    function promptId() {
+        return new URL(opened[opened.length - 1]).searchParams.get("approval");
+    }
+
+    // What the popup is told to show for the prompt.
+    function describePrompt() {
+        let reply = null;
+        messageListener(
+            { type: "AUTISTMASK_GET_APPROVAL", id: promptId() },
+            { url: EXT_URL + "src/popup/index.html" },
+            (r) => {
+                reply = r;
+            },
+        );
+        return reply;
+    }
+
+    // The user's answer, as the popup sends it: on the port named for the
+    // approval, from the extension's own page, and then the window closes.
+    async function answerPrompt(approved) {
+        const onMessage = [];
+        const onDisconnect = [];
+        const port = {
+            name: "approval:" + promptId(),
+            sender: { url: EXT_URL + "src/popup/index.html" },
+            onMessage: { addListener: (fn) => onMessage.push(fn) },
+            onDisconnect: { addListener: (fn) => onDisconnect.push(fn) },
+        };
+        connectListener(port);
+        for (const fn of onMessage) {
+            fn(
+                {
+                    type: "AUTISTMASK_APPROVAL_DECISION",
+                    approved,
+                    remember: false,
+                },
+                port,
+            );
+        }
+        for (const fn of onDisconnect) fn(port);
+        await settle();
+    }
+
+    // The user closes the prompt window without answering it.
+    async function closePrompt() {
+        windowRemovedListener(opened.length);
+        await settle();
     }
 
     return {
         switchChain,
+        describePrompt,
+        answerPrompt,
+        closePrompt,
+        opened,
         walletState: () => storage.read("autistmask"),
         chainChangedEvents: () =>
             toTabs.filter((m) => m.eventName === "chainChanged"),
     };
 }
 
+const USER_REJECTED = { code: 4001, message: "User rejected the request." };
+
 describe("wallet_switchEthereumChain is gated on the connection", () => {
     test("an origin the wallet was never connected to is refused with 4100", async () => {
         const bg = loadBackground();
+        const before = bg.walletState();
 
-        const result = await bg.switchChain(SEPOLIA.chainId, STRANGER_ORIGIN);
+        const request = await bg.switchChain(SEPOLIA.chainId, STRANGER_ORIGIN);
 
-        expect(result.error).toEqual({ code: 4100, message: "Unauthorized" });
-        expect(result.result).toBeUndefined();
+        expect(request.result().error).toEqual({
+            code: 4100,
+            message: "Unauthorized",
+        });
+        expect(request.result().result).toBeUndefined();
         // The refusal has to be a refusal to ACT, not just an error string:
         // the wallet is still on mainnet, still on the user's own node, and
-        // no page was told the chain moved.
-        expect(bg.walletState().networkId).toBe("mainnet");
-        expect(bg.walletState().rpcUrl).toBe(CUSTOM_RPC);
+        // no page was told the chain moved. Nor was the user asked.
+        expect(bg.walletState()).toEqual(before);
         expect(bg.chainChangedEvents()).toEqual([]);
+        expect(bg.opened).toEqual([]);
     });
 
     test("an unconnected origin is refused even for the chain already active", async () => {
         const bg = loadBackground();
 
-        const result = await bg.switchChain(MAINNET.chainId, STRANGER_ORIGIN);
+        const request = await bg.switchChain(MAINNET.chainId, STRANGER_ORIGIN);
 
-        expect(result.error).toEqual({ code: 4100, message: "Unauthorized" });
+        expect(request.result().error).toEqual({
+            code: 4100,
+            message: "Unauthorized",
+        });
     });
 
     test("an unconnected origin is refused before the unsupported-chain answer", async () => {
         const bg = loadBackground();
 
-        const result = await bg.switchChain("0x89", STRANGER_ORIGIN);
+        const request = await bg.switchChain("0x89", STRANGER_ORIGIN);
 
-        expect(result.error.code).toBe(4100);
+        expect(request.result().error.code).toBe(4100);
+    });
+});
+
+describe("only the user switches the network", () => {
+    test("a connected site's request changes nothing while the prompt is open", async () => {
+        const bg = loadBackground();
+        const before = bg.walletState();
+
+        const request = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+
+        // Waiting on the user, with one prompt on screen naming the site and
+        // both networks.
+        expect(request.result()).toBeNull();
+        expect(bg.opened).toHaveLength(1);
+        expect(bg.describePrompt()).toMatchObject({
+            origin: CONNECTED_ORIGIN,
+            type: "network",
+            currentNetworkId: "mainnet",
+            requestedNetworkId: "sepolia",
+        });
+
+        // The network, the endpoints and the balances are as they were, and
+        // no page was told otherwise.
+        expect(bg.walletState()).toEqual(before);
+        expect(bg.chainChangedEvents()).toEqual([]);
     });
 
-    test("a connected origin switches the chain", async () => {
+    test("approving the prompt switches the network", async () => {
         const bg = loadBackground();
 
-        const result = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+        const request = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+        await bg.answerPrompt(true);
 
-        expect(result).toEqual({ result: null });
-        expect(bg.walletState().networkId).toBe("sepolia");
+        expect(request.result()).toEqual({ result: null });
+        const after = bg.walletState();
+        expect(after.networkId).toBe("sepolia");
+        expect(after.rpcUrl).toBe(SEPOLIA.defaultRpcUrl);
+        expect(after.wallets[0].addresses[0].balance).toBe("0");
         expect(bg.chainChangedEvents()).toEqual([
             {
                 type: "AUTISTMASK_EVENT",
@@ -201,22 +317,76 @@ describe("wallet_switchEthereumChain is gated on the connection", () => {
         ]);
     });
 
-    test("a connected origin asking for an unsupported chain still gets 4902", async () => {
+    test("rejecting the prompt changes nothing and answers 4001", async () => {
+        const bg = loadBackground();
+        const before = bg.walletState();
+
+        const request = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+        await bg.answerPrompt(false);
+
+        expect(request.result()).toEqual({ error: USER_REJECTED });
+        expect(bg.walletState()).toEqual(before);
+        expect(bg.chainChangedEvents()).toEqual([]);
+    });
+
+    test("closing the prompt without answering changes nothing and answers 4001", async () => {
+        const bg = loadBackground();
+        const before = bg.walletState();
+
+        const request = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+        await bg.closePrompt();
+
+        expect(request.result()).toEqual({ error: USER_REJECTED });
+        expect(bg.walletState()).toEqual(before);
+        expect(bg.chainChangedEvents()).toEqual([]);
+    });
+
+    test("a request for the chain already active opens no prompt", async () => {
+        const bg = loadBackground();
+        const before = bg.walletState();
+
+        const request = await bg.switchChain(MAINNET.chainId, CONNECTED_ORIGIN);
+
+        expect(request.result()).toEqual({ result: null });
+        expect(bg.opened).toEqual([]);
+        expect(bg.walletState()).toEqual(before);
+        expect(bg.chainChangedEvents()).toEqual([]);
+    });
+
+    test("a second request while the prompt is open is refused with -32002", async () => {
         const bg = loadBackground();
 
-        const result = await bg.switchChain("0x89", CONNECTED_ORIGIN);
+        const first = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+        const second = await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
 
-        expect(result.error.code).toBe(4902);
+        expect(second.result().error.code).toBe(-32002);
+        expect(bg.opened).toHaveLength(1);
+
+        // The first prompt still decides.
+        await bg.answerPrompt(true);
+        expect(first.result()).toEqual({ result: null });
+        expect(bg.walletState().networkId).toBe("sepolia");
+    });
+
+    test("a request for an unsupported chain still gets 4902 and no prompt", async () => {
+        const bg = loadBackground();
+
+        const request = await bg.switchChain("0x89", CONNECTED_ORIGIN);
+
+        expect(request.result().error.code).toBe(4902);
+        expect(bg.opened).toEqual([]);
         expect(bg.walletState().networkId).toBe("mainnet");
     });
 
-    test("a switch by a connected origin keeps the user's endpoint", async () => {
+    test("an approved switch keeps the user's endpoint", async () => {
         const bg = loadBackground();
 
         await bg.switchChain(SEPOLIA.chainId, CONNECTED_ORIGIN);
+        await bg.answerPrompt(true);
         expect(bg.walletState().rpcUrl).toBe(SEPOLIA.defaultRpcUrl);
 
         await bg.switchChain(MAINNET.chainId, CONNECTED_ORIGIN);
+        await bg.answerPrompt(true);
         expect(bg.walletState().rpcUrl).toBe(CUSTOM_RPC);
     });
 });

tests/coldWorkerChainSwitch.test.js

@@ -14,6 +14,10 @@
 // itself: the handler has to do it. tests/chainSwitchGate.test.js mocks the
 // state module wholesale and tests/networkEndpoints.test.js always loads
 // first, so neither can see this.
+//
+// A site's switch happens only once the user approves it on a prompt
+// (https://git.eeqj.de/sneak/AutistMask/issues/408), so every switch here is
+// approved the way the popup approves one.
 
 const { networkById } = require("../src/shared/networks");
 const { makeStorageStub } = require("./support/storageStub");
@@ -90,6 +94,9 @@ function loadColdWorker(networkId) {
     const storage = makeStorageStub({ autistmask: storedProfile(networkId) });
 
     let messageListener = null;
+    let connectListener = null;
+    // The URL of every approval window opened; the approval id is in it.
+    const opened = [];
     const toTabs = [];
 
     global.chrome = {
@@ -101,12 +108,19 @@ function loadColdWorker(networkId) {
                     messageListener = fn;
                 },
             },
-            onConnect: { addListener: () => {} },
+            onConnect: {
+                addListener: (fn) => {
+                    connectListener = fn;
+                },
+            },
             lastError: null,
         },
         windows: {
             getLastFocused: (cb) => cb(null),
-            create: (options, cb) => cb({ id: 1 }),
+            create: (options, cb) => {
+                opened.push(options.url);
+                cb({ id: opened.length });
+            },
             remove: (id, cb) => {
                 if (cb) cb();
             },
@@ -124,6 +138,32 @@ function loadColdWorker(networkId) {
 
     require("../src/background/index");
 
+    // The user approves the prompt the request opened, as the popup does: a
+    // decision on the port named for the approval, from the extension's own
+    // page.
+    function approvePrompt() {
+        const id = new URL(opened[opened.length - 1]).searchParams.get(
+            "approval",
+        );
+        let onDecision = null;
+        const port = {
+            name: "approval:" + id,
+            sender: { url: "chrome-extension://autistmask/src/popup/" },
+            onMessage: {
+                addListener: (fn) => {
+                    onDecision = fn;
+                },
+            },
+            onDisconnect: { addListener: () => {} },
+        };
+        connectListener(port);
+        onDecision(
+            { type: "AUTISTMASK_APPROVAL_DECISION", approved: true },
+            port,
+        );
+    }
+
+    // A connected site asks for `chainId`, and the user approves it.
     async function switchChain(chainId) {
         let result = null;
         messageListener(
@@ -138,6 +178,8 @@ function loadColdWorker(networkId) {
             },
         );
         await settle();
+        approvePrompt();
+        await settle();
         return result;
     }
 

tests/deleteWalletLostPassword.test.js

@@ -253,7 +253,7 @@ describe("reaching the screen", () => {
         const { decryptWithPassword } = require("../src/shared/vault");
         decryptWithPassword.mockRejectedValue(new Error("nope"));
         await click("btn-delete-wallet-confirm");
-        expect(node("delete-wallet-flash").textContent).toBe(
+        expect(node("delete-wallet-password-error").textContent).toBe(
             "That password is incorrect. Please try again.",
         );
     });
@@ -618,9 +618,11 @@ describe("the password route's confirm button", () => {
 
 // https://git.eeqj.de/sneak/AutistMask/issues/480: leaving either delete
 // screen drops its wallet selection, so Back onto one showed a screen whose
-// button could only answer "No wallet selected for deletion."
+// button could only answer "No wallet selected for deletion." Taking the
+// screen off the stack leaves Settings under Settings, and Back must not land
+// there either (https://git.eeqj.de/sneak/AutistMask/issues/481).
 describe("Back from Settings after leaving by the settings gear", () => {
-    test("does not land on the delete screen", () => {
+    test("goes past the delete screen to the screen under Settings", () => {
         const { helpers, deleteWallet, state } = load();
         deleteWallet.show(1);
         // The settings gear: push the current view, then show Settings.
@@ -629,10 +631,10 @@ describe("Back from Settings after leaving by the settings gear", () => {
 
         expect(state.viewStack).toEqual(["main", "settings"]);
         helpers.goBack();
-        expect(state.currentView).not.toBe("delete-wallet-confirm");
+        expect(state.currentView).toBe("main");
     });
 
-    test("does not land on the lost-password screen", async () => {
+    test("goes past the lost-password screen to the screen under Settings", async () => {
         const { helpers, deleteWallet, state } = load();
         await openLostPassword(deleteWallet, 1);
         // The settings gear: push the current view, then show Settings.
@@ -641,7 +643,7 @@ describe("Back from Settings after leaving by the settings gear", () => {
 
         expect(state.viewStack).toEqual(["main", "settings"]);
         helpers.goBack();
-        expect(state.currentView).not.toBe(VIEW);
+        expect(state.currentView).toBe("main");
     });
 
     // The lost-password screen's own Back is "Back returns to the delete

tests/e2e/firefox/run.js

@@ -63,6 +63,7 @@ const {
 const { ConsoleErrors, EXTENSION_ORIGIN, start, sleep } = require("./driver");
 const { startDappServer } = require("./dapp");
 const { STUB_COUNTERPARTY } = require("../network");
+const { NETWORKS } = require("../../../src/shared/networks");
 const {
     STATE_SCHEMA_VERSION,
     stateProblem,
@@ -684,6 +685,159 @@ step(
     },
 );
 
+// The network fields of the stored record, read on the popup page, the one
+// moz-extension:// document the suite has open.
+async function storedNetwork(env) {
+    const d = env.driver;
+    await d.switchToWindow(env.popupWindow);
+    const stored = await d.executeAsync(
+        `const done = arguments[arguments.length - 1];
+         const api = typeof browser !== "undefined" ? browser : chrome;
+         Promise.resolve(api.storage.local.get("autistmask")).then(
+             (r) => done({
+                 networkId: r.autistmask.networkId,
+                 rpcUrl: r.autistmask.rpcUrl,
+                 blockscoutUrl: r.autistmask.blockscoutUrl,
+             }),
+             (e) => done({ error: String((e && e.message) || e) }),
+         );`,
+    );
+    assert(
+        stored && !stored.error,
+        "could not read the stored network: " + (stored && stored.error),
+    );
+    return stored;
+}
+
+// Every chainChanged event the test page has been sent, waiting up to
+// `timeout` for there to be `count` of them: the background sends the event
+// alongside its answer to the request, so it can arrive just after it. Leaves
+// the driver on the page.
+async function chainChangedEvents(env, count = 0, timeout = 5000) {
+    const d = env.driver;
+    await d.switchToWindow(env.dappWindow);
+    const deadline = Date.now() + timeout;
+    for (;;) {
+        const events = (await dappMessages(d, "AUTISTMASK_EVENT")).filter(
+            (m) => m.eventName === "chainChanged",
+        );
+        if (events.length >= count || Date.now() > deadline) return events;
+        await sleep(100);
+    }
+}
+
+// Ask, from the page, to switch from network `from` to network `to`, and
+// return the prompt that opens, checked to name the site and both networks.
+// Leaves the driver on the prompt.
+async function openNetworkPrompt(env, key, from, to) {
+    const d = env.driver;
+    await d.switchToWindow(env.dappWindow);
+    await startRequest(d, key, "wallet_switchEthereumChain", [
+        { chainId: to.chainId },
+    ]);
+    const popup = await waitForApprovalWindow(d);
+    await d.switchToWindow(popup);
+    await d.waitVisible("#view-approve-network");
+    const screen = {
+        origin: await d.text("#approve-network-origin"),
+        current: await d.text("#approve-network-current"),
+        requested: await d.text("#approve-network-requested"),
+    };
+    assert(
+        isDeepStrictEqual(screen, {
+            origin: env.server.origin,
+            current: from.name,
+            requested: to.name,
+        }),
+        "the network switch prompt shows " + JSON.stringify(screen),
+    );
+    return popup;
+}
+
+// Only the user switches the network. A connected site's request opens a
+// prompt, and until the user approves it the stored network does not move and
+// no page is told it did (https://git.eeqj.de/sneak/AutistMask/issues/408).
+// The wallet goes back to mainnet the same way at the end, for the transaction
+// step after this one.
+step(
+    "a site's network switch changes nothing until the user approves it",
+    async (env) => {
+        const d = env.driver;
+        const { mainnet, sepolia } = NETWORKS;
+        const before = await storedNetwork(env);
+        assert(
+            before.networkId === "mainnet",
+            "this step starts on mainnet, not on " + before.networkId,
+        );
+        const eventsBefore = (await chainChangedEvents(env)).length;
+
+        const rejected = await openNetworkPrompt(
+            env,
+            "switch-reject",
+            mainnet,
+            sepolia,
+        );
+        assert(
+            isDeepStrictEqual(await storedNetwork(env), before),
+            "the network moved while its prompt was still open",
+        );
+        // Nothing else closes this window, so a click that did not land
+        // leaves the request unanswered and the assertion below fails.
+        await d.switchToWindow(rejected);
+        await d.click("#btn-reject-network");
+        await d.switchToWindow(env.dappWindow);
+        await assertUserRejection(
+            d,
+            "switch-reject",
+            "the network switch rejection",
+        );
+        assert(
+            isDeepStrictEqual(await storedNetwork(env), before),
+            "a rejected network switch moved the network",
+        );
+        assert(
+            (await chainChangedEvents(env)).length === eventsBefore,
+            "a rejected network switch told the page the chain changed",
+        );
+
+        await openNetworkPrompt(env, "switch-approve", mainnet, sepolia);
+        await d.click("#btn-approve-network");
+        await d.switchToWindow(env.dappWindow);
+        let outcome = await settleRequest(d, "switch-approve");
+        assert(
+            outcome.settled === "resolved" && outcome.result === null,
+            "the approved network switch did not resolve: " +
+                JSON.stringify(outcome),
+        );
+        assert(
+            (await storedNetwork(env)).networkId === "sepolia",
+            "the approved network switch did not move the network",
+        );
+        const events = await chainChangedEvents(env, eventsBefore + 1);
+        assert(
+            events.length === eventsBefore + 1 &&
+                events[events.length - 1].data === sepolia.chainId,
+            "the page was not told of the approved switch: " +
+                JSON.stringify(events),
+        );
+
+        await openNetworkPrompt(env, "switch-restore", sepolia, mainnet);
+        await d.click("#btn-approve-network");
+        await d.switchToWindow(env.dappWindow);
+        outcome = await settleRequest(d, "switch-restore");
+        assert(
+            outcome.settled === "resolved",
+            "switching back to mainnet did not resolve: " +
+                JSON.stringify(outcome),
+        );
+        assert(
+            isDeepStrictEqual(await storedNetwork(env), before),
+            "switching back did not restore the mainnet network and endpoints",
+        );
+        await d.switchToWindow(env.dappWindow);
+    },
+);
+
 step(
     "eth_sendTransaction shows the transaction and returns its hash",
     async (env) => {
@@ -854,37 +1008,6 @@ step(
 
 // ------------------------------------------------------------- runner
 
-// Uncaught extension errors that are known, tracked and deliberately
-// tolerated, in the same spirit as ALLOWED_ERRORS in tests/e2e/harness.js:
-// every entry names the issue that will delete it, and every occurrence is
-// still printed, so tolerating one is visible in the log rather than silent.
-// This is the only concession in an otherwise zero-tolerance policy.
-const ALLOWED_ERRORS = [
-    {
-        // The site-connection buttons in src/popup/views/approval.js send
-        // their decision and call window.close() on the next line. Firefox's
-        // BaseContext.wrapPromise reports, through Cu.reportError, any
-        // extension-API promise that settles after its context unloaded —
-        // whether or not the caller attached a handler, so notify()'s catch
-        // cannot suppress it.
-        //
-        // Pre-existing, and not introduced by the promise shim: the send was
-        // already unawaited, and this suite is merely the first thing to
-        // drive that window on Firefox. It is the same teardown ordering as
-        // the issue below, whose fix — making the outcome independent of when
-        // the popup closes — removes this entry with it.
-        pattern: /Promise (?:resolved|rejected) after context unloaded/,
-        source: /\/src\/popup\/index\.js$/,
-        issue: "https://git.eeqj.de/sneak/AutistMask/issues/275",
-    },
-];
-
-function allowedFor(e) {
-    return ALLOWED_ERRORS.find(
-        (a) => a.pattern.test(e.msg) && a.source.test(e.src),
-    );
-}
-
 function formatError(e) {
     return (
         e.msg + " (" + e.src + ":" + e.line + (e.cat ? ", " + e.cat : "") + ")"
@@ -1001,20 +1124,6 @@ async function main() {
                 installFailure = null;
             }
 
-            // Tolerated errors are set aside, never dropped: each one is
-            // printed with the issue that keeps it on the list, so the
-            // concession stays in the run output.
-            const tolerated = found.filter((e) => allowedFor(e));
-            found = found.filter((e) => !allowedFor(e));
-            for (const e of tolerated) {
-                console.log(
-                    "# tolerated (" +
-                        allowedFor(e).issue +
-                        "): " +
-                        formatError(e),
-                );
-            }
-
             // Any uncaught error from an extension source fails the step
             // that provoked it, whether or not its assertions passed.
             if (!failure && found.length > 0) {
@@ -1039,13 +1148,7 @@ async function main() {
         // blamed on any one step, but they are still reported and they
         // still fail the run.
         await sleep(1000);
-        const trailingAll = await errors.take();
-        for (const e of trailingAll.filter((x) => allowedFor(x))) {
-            console.log(
-                "# tolerated (" + allowedFor(e).issue + "): " + formatError(e),
-            );
-        }
-        const trailing = trailingAll.filter((e) => !allowedFor(e));
+        const trailing = await errors.take();
         console.log(
             "# " +
                 (steps.length - failed) +

tests/e2e/run.js

@@ -809,7 +809,7 @@ async function secretScreenState(page, view) {
     return page.evaluate(
         (v) => ({
             value: document.getElementById(v + "-value").textContent,
-            error: document.getElementById(v + "-flash").textContent,
+            error: document.getElementById(v + "-password-error").textContent,
             html: document.getElementById("view-" + v).innerHTML,
             resultHidden: document
                 .getElementById(v + "-result")
@@ -906,7 +906,8 @@ test("a wrong password reveals nothing (#161)", async (env) => {
     await env.page.click("#btn-show-phrase-reveal");
     await env.page.waitForFunction(
         () =>
-            document.getElementById("show-phrase-flash").textContent.length > 0,
+            document.getElementById("show-phrase-password-error").textContent
+                .length > 0,
         null,
         { timeout: 60000 },
     );
@@ -1993,13 +1994,14 @@ test("an over-long flash message keeps to one line (#252)", async (env) => {
 
 // Every screen that asks for a password reserves room for one line of error.
 // The two on the dApp approval screens also have a border and padding, which
-// that reserved height has to cover too.
+// that reserved height has to cover too. The add wallet screen's line sits
+// beside its button rather than above it, and has its own test below.
 const PASSWORD_ERROR_CONTAINERS = [
     "approve-tx-error",
     "approve-sign-error",
-    "export-privkey-flash",
-    "show-phrase-flash",
-    "delete-wallet-flash",
+    "export-privkey-password-error",
+    "show-phrase-password-error",
+    "delete-wallet-password-error",
     "confirm-tx-password-error",
 ];
 
@@ -2064,6 +2066,107 @@ test("a password error moves nothing on any screen (#297)", async (env) => {
     }
 });
 
+// ------------------------------------------ add wallet Import button (#493)
+
+// At 360x600 the add wallet screen's Import button already starts near the
+// bottom of the popup, so its password error line sits beside the button
+// rather than above it. Measures the button and the line empty and again
+// filled with the longest error addWallet.js puts there. Runs in the page.
+function measureImportButton() {
+    const button = document.getElementById("btn-add-wallet-confirm");
+    const line = document.getElementById("add-wallet-password-error");
+    const measure = () => {
+        const b = button.getBoundingClientRect();
+        const l = line.getBoundingClientRect();
+        return {
+            buttonTop: b.top + window.scrollY,
+            buttonBottom: b.bottom + window.scrollY,
+            lineTop: l.top + window.scrollY,
+            lineBottom: l.bottom + window.scrollY,
+        };
+    };
+    const empty = measure();
+    line.textContent = "Password must be at least 12 characters.";
+    line.style.visibility = "visible";
+    const filled = measure();
+    line.textContent = "";
+    line.style.visibility = "hidden";
+    return { empty, filled };
+}
+
+test("the add wallet password error leaves Import where it was (#493)", async (env) => {
+    const page = await openPopup(env.ctx, env.popupUrl);
+    try {
+        await page.setViewportSize(POPUP_VIEWPORT);
+        // Brought up by toggling classes, as in the test above. The note
+        // addWallet.js shows once a wallet exists is the only part of the
+        // screen that differs between the first wallet and a later one.
+        await page.evaluate(() => {
+            const screen = document.getElementById("view-add-wallet");
+            for (const view of document.querySelectorAll(".view")) {
+                view.classList.toggle("hidden", view !== screen);
+            }
+        });
+        for (const walletExists of [false, true]) {
+            await page.evaluate(
+                (shown) =>
+                    document
+                        .getElementById("add-wallet-separate-password-note")
+                        .classList.toggle("hidden", !shown),
+                walletExists,
+            );
+            for (const tab of ["tab-mnemonic", "tab-privkey", "tab-xprv"]) {
+                await page.click("#" + tab);
+                const { empty, filled } =
+                    await page.evaluate(measureImportButton);
+                const where =
+                    "#" +
+                    tab +
+                    (walletExists
+                        ? " with a wallet already added"
+                        : " for the first wallet");
+                // Printed pass or fail, as the dust threshold test does.
+                console.log(
+                    "# add wallet Import top, " +
+                        where +
+                        ": " +
+                        empty.buttonTop +
+                        "px",
+                );
+                for (const m of [empty, filled]) {
+                    assert(
+                        m.lineTop >= m.buttonTop &&
+                            m.lineBottom <= m.buttonBottom,
+                        "the error line on " +
+                            where +
+                            " does not fit beside Import, so it adds height: " +
+                            JSON.stringify(m),
+                    );
+                }
+                assert(
+                    filled.buttonTop === empty.buttonTop,
+                    "Import moved " +
+                        (filled.buttonTop - empty.buttonTop) +
+                        "px when the error appeared on " +
+                        where,
+                );
+                if (!walletExists) {
+                    assert(
+                        empty.buttonTop < POPUP_VIEWPORT.height,
+                        "Import starts at " +
+                            empty.buttonTop +
+                            "px on " +
+                            where +
+                            ", below the fold",
+                    );
+                }
+            }
+        }
+    } finally {
+        await page.close();
+    }
+});
+
 // --------------------------------------------- confirmation screen (#238)
 //
 // The screen that decides what gets signed. The arithmetic underneath it
@@ -3396,7 +3499,7 @@ async function closeApprovalPages(ctx) {
 }
 
 // Click a button whose own handler closes the window it lives in — every
-// Reject, and Allow on the site prompt.
+// Reject, Allow on the site prompt, and Switch on the network switch prompt.
 //
 // page.click() dispatches the click and then waits for the renderer to
 // acknowledge it, and a page torn down by the handler never gets to. The
@@ -3411,12 +3514,13 @@ async function closeApprovalPages(ctx) {
 //   #btn-reject-sign, #btn-reject-tx — their disconnect leaves the approval
 //     pending, so a click that never landed leaves the dApp promise unsettled
 //     and the assertion after the call fails on its own.
-//   #btn-approve — only a decision resolves the promise, and a swallowed click
-//     cannot produce settled === "resolved".
-//   #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. Both call sites arm the click trace below and assert it.
+//   #btn-approve, #btn-approve-network — only a decision resolves the promise,
+//     and a swallowed click cannot produce settled === "resolved".
+//   #btn-reject on the site prompt, #btn-reject-network — 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. Every call site arms the click trace below
+//     and asserts it.
 //
 // A button that is missing or unclickable raises a different error, which is
 // rethrown.
@@ -4286,6 +4390,154 @@ test("a prompt raised while another approval window has focus opens its own (#29
     await assertUserRejection(env.dapp, "focus-sign", "the sign prompt");
 });
 
+// The network fields of the stored record.
+async function storedNetwork(page) {
+    const s = await storedRecord(page);
+    return {
+        networkId: s.networkId,
+        rpcUrl: s.rpcUrl,
+        blockscoutUrl: s.blockscoutUrl,
+    };
+}
+
+// Every chainChanged event the test page has been sent, waiting up to
+// `timeout` for there to be `count` of them: the background sends the event
+// alongside its answer to the request, so it can arrive just after it.
+async function chainChangedEvents(page, count = 0, timeout = 5000) {
+    const deadline = Date.now() + timeout;
+    for (;;) {
+        const events = (await dappMessages(page, "AUTISTMASK_EVENT")).filter(
+            (m) => m.eventName === "chainChanged",
+        );
+        if (events.length >= count || Date.now() > deadline) return events;
+        await sleep(50);
+    }
+}
+
+// Ask, from the test page, to switch from network `from` to network `to`, and
+// return the prompt that opens, checked to name the site and both networks.
+async function openNetworkPrompt(env, key, from, to) {
+    await startRequest(env.dapp, key, "wallet_switchEthereumChain", [
+        { chainId: to.chainId },
+    ]);
+    const popup = await waitForApprovalWindow(env.ctx);
+    await visible(popup, "#view-approve-network");
+    const screen = await popup.evaluate(() => ({
+        origin: document.getElementById("approve-network-origin").textContent,
+        current: document.getElementById("approve-network-current").textContent,
+        requested: document.getElementById("approve-network-requested")
+            .textContent,
+    }));
+    assert(
+        isDeepStrictEqual(screen, {
+            origin: DAPP_ORIGIN,
+            current: from.name,
+            requested: to.name,
+        }),
+        "the network switch prompt shows " + JSON.stringify(screen),
+    );
+    return popup;
+}
+
+// Only the user switches the network. A connected site's request opens a
+// prompt, and until the user approves it the stored network does not move and
+// no page is told it did (https://git.eeqj.de/sneak/AutistMask/issues/408).
+// The wallet goes back to mainnet the same way at the end, for the tests after
+// this one.
+test("a site's network switch changes nothing until the user approves it (#408)", async (env) => {
+    const { mainnet, sepolia } = NETWORKS;
+    const before = await storedNetwork(env.page);
+    assert(
+        before.networkId === "mainnet",
+        "this test starts on mainnet, not on " + before.networkId,
+    );
+    const eventsBefore = (await chainChangedEvents(env.dapp)).length;
+
+    const rejected = await openNetworkPrompt(
+        env,
+        "switch-reject",
+        mainnet,
+        sepolia,
+    );
+    try {
+        assert(
+            isDeepStrictEqual(await storedNetwork(env.page), before),
+            "the network moved while its prompt was still open",
+        );
+        // Closing the prompt unanswered is also a rejection, so the click
+        // itself is witnessed.
+        await armClickTrace(env, rejected, "#btn-reject-network");
+        await clickAndClose(rejected, "#btn-reject-network");
+        await assertClickLanded(env, "#btn-reject-network");
+        await assertUserRejection(
+            env.dapp,
+            "switch-reject",
+            "the network switch rejection",
+        );
+    } finally {
+        await closeApprovalPages(env.ctx);
+    }
+    assert(
+        isDeepStrictEqual(await storedNetwork(env.page), before),
+        "a rejected network switch moved the network",
+    );
+    assert(
+        (await chainChangedEvents(env.dapp)).length === eventsBefore,
+        "a rejected network switch told the page the chain changed",
+    );
+
+    const approved = await openNetworkPrompt(
+        env,
+        "switch-approve",
+        mainnet,
+        sepolia,
+    );
+    let outcome;
+    try {
+        await clickAndClose(approved, "#btn-approve-network");
+        outcome = await settleRequest(env.dapp, "switch-approve");
+    } finally {
+        await closeApprovalPages(env.ctx);
+    }
+    assert(
+        outcome.settled === "resolved" && outcome.result === null,
+        "the approved network switch did not resolve: " +
+            JSON.stringify(outcome),
+    );
+    assert(
+        (await storedNetwork(env.page)).networkId === "sepolia",
+        "the approved network switch did not move the network",
+    );
+    const events = await chainChangedEvents(env.dapp, eventsBefore + 1);
+    assert(
+        events.length === eventsBefore + 1 &&
+            events[events.length - 1].data === sepolia.chainId,
+        "the page was not told of the approved switch: " +
+            JSON.stringify(events),
+    );
+
+    const restored = await openNetworkPrompt(
+        env,
+        "switch-restore",
+        sepolia,
+        mainnet,
+    );
+    try {
+        await clickAndClose(restored, "#btn-approve-network");
+        outcome = await settleRequest(env.dapp, "switch-restore");
+    } finally {
+        await closeApprovalPages(env.ctx);
+    }
+    assert(
+        outcome.settled === "resolved",
+        "switching back to mainnet did not resolve: " + JSON.stringify(outcome),
+    );
+    assert(
+        isDeepStrictEqual(await storedNetwork(env.page), before),
+        "switching back did not restore the mainnet network and endpoints",
+    );
+});
+
 // The closing pass over both boundaries at once. Every message the section
 // put on either channel is re-read here and required to be free of the
 // password — and required to be there at all, method by method, so the

tests/exportPrivkey.test.js

@@ -207,7 +207,7 @@ describe("a decrypt still running when the screen is left", () => {
     });
 
     // Same hole on the failure path: a wrong-password error written after
-    // the wipe would restore the flash line on a screen the user has left.
+    // the wipe would restore the error line on a screen the user has left.
     test("never writes the failure message either", async () => {
         const { helpers, vault, exportPrivkey } = load();
         exportPrivkey.show(0, 0);
@@ -217,8 +217,10 @@ describe("a decrypt still running when the screen is left", () => {
         reveal.reject(new Error("decryption failed"));
         await reveal.pending;
 
-        expect(node("export-privkey-flash").textContent).toBe("");
-        expect(node("export-privkey-flash").style.visibility).toBe("hidden");
+        expect(node("export-privkey-password-error").textContent).toBe("");
+        expect(node("export-privkey-password-error").style.visibility).toBe(
+            "hidden",
+        );
     });
 });
 
@@ -260,7 +262,7 @@ describe("a reveal that is not interrupted", () => {
         await reveal.pending;
 
         expect(node("export-privkey-value").textContent).toBe("");
-        expect(node("export-privkey-flash").textContent).toBe(
+        expect(node("export-privkey-password-error").textContent).toBe(
             "That password is incorrect. Please try again.",
         );
     });

tests/icons.test.js

@@ -0,0 +1,33 @@
+// The toolbar icons in icons/ are drawn by script/lib/icons.js (`make icons`).
+// Each committed file must hold exactly the image it draws, the same IHDR and
+// every pixel, so the drawing and the files cannot drift apart. The compressed
+// bytes are not compared: the committed files were compressed by stock zlib,
+// and node's bundled zlib compresses the same pixels differently.
+
+const fs = require("fs");
+const path = require("path");
+
+const { icons } = require("../manifest/chrome.json");
+const { drawIcon, decodePng } = require("../script/lib/icons");
+
+describe("toolbar icons", () => {
+    test.each(Object.entries(icons))(
+        "the %spx icon %s holds the image script/lib/icons.js draws",
+        (size, file) => {
+            const side = Number(size);
+            const committed = decodePng(
+                fs.readFileSync(path.join(__dirname, "..", file)),
+            );
+            const drawn = decodePng(drawIcon(side));
+
+            expect(committed.header).toEqual(drawn.header);
+            // Each row is its filter type byte, then 4 bytes per pixel.
+            expect(drawn.rows.length).toBe(side * (side * 4 + 1));
+            expect(committed.rows.length).toBe(drawn.rows.length);
+            // The offset of the first byte that differs, not a diff of all.
+            expect(
+                committed.rows.findIndex((byte, i) => byte !== drawn.rows[i]),
+            ).toBe(-1);
+        },
+    );
+});

tests/passwordErrorLines.test.js

@@ -0,0 +1,159 @@
+// Every screen that asks for a password shows a password error the same way:
+// through showError() and hideError() in src/popup/views/helpers.js, in a
+// fixed-height error line below the password field, and never in the flash
+// line at the top of the popup
+// (https://git.eeqj.de/sneak/AutistMask/issues/493). These boot the real popup
+// over src/popup/index.html, so each error line has to exist in the markup,
+// and check that the error appears in it and clears again.
+
+jest.mock("../src/shared/vault", () => ({
+    decryptWithPassword: jest.fn(),
+    encryptWithPassword: jest.fn(),
+}));
+
+const {
+    bootPopup,
+    cleanupPopup,
+    unversionedValidProfile,
+} = require("./support/popupBoot");
+
+const PASSWORD = "correct horse battery staple";
+const WRONG_PASSWORD = "That password is incorrect. Please try again.";
+
+afterEach(() => {
+    cleanupPopup();
+});
+
+// The error line as the user sees it.
+function errorLine(page, id) {
+    return {
+        inMarkup: page.document.authoredIds.has(id),
+        text: page.text(id),
+        visibility: page.node(id).style.visibility,
+    };
+}
+
+function shown(text) {
+    return { inMarkup: true, text, visibility: "visible" };
+}
+
+const cleared = { inMarkup: true, text: "", visibility: "hidden" };
+
+describe("the add wallet screen", () => {
+    const ERROR = "add-wallet-password-error";
+
+    // First run: Welcome, "Add wallet", then the die for a valid phrase.
+    async function openAddWallet() {
+        const page = await bootPopup(undefined);
+        await page.click("btn-welcome-add");
+        await page.click("btn-generate-phrase");
+        return page;
+    }
+
+    function setPasswords(page, password, confirm) {
+        page.node("add-wallet-password").value = password;
+        page.node("add-wallet-password-confirm").value = confirm;
+    }
+
+    test("shows a password problem below the password fields, and clears it on the next press", async () => {
+        const page = await openAddWallet();
+        setPasswords(page, "short", "short");
+        await page.click("btn-add-wallet-confirm");
+        expect(errorLine(page, ERROR)).toEqual(
+            shown("Password must be at least 12 characters."),
+        );
+        expect(page.text("flash-msg")).toBe("");
+
+        // The password is fixed and the phrase emptied: the password error
+        // goes, and the phrase problem is still reported in the flash line.
+        setPasswords(page, PASSWORD, PASSWORD);
+        page.node("wallet-mnemonic").value = "";
+        await page.click("btn-add-wallet-confirm");
+        expect(errorLine(page, ERROR)).toEqual(cleared);
+        expect(page.text("flash-msg")).toBe(
+            "Enter a recovery phrase, or press the die.",
+        );
+
+        // Leaving clears the flash line and stops its timer, which would
+        // otherwise fire after this page is gone.
+        await page.click("btn-add-wallet-back");
+    });
+
+    test("clears the error when the screen is shown again", async () => {
+        const page = await openAddWallet();
+        setPasswords(page, PASSWORD, PASSWORD + " typo");
+        await page.click("btn-add-wallet-confirm");
+        expect(errorLine(page, ERROR)).toEqual(
+            shown("Passwords do not match."),
+        );
+
+        await page.click("btn-add-wallet-back");
+        await page.click("btn-welcome-add");
+        expect(errorLine(page, ERROR)).toEqual(cleared);
+    });
+});
+
+describe.each([
+    {
+        screen: "the private key export screen",
+        open: () => require("../src/popup/views/exportPrivkey").show(0, 0),
+        field: "export-privkey-password",
+        button: "btn-export-privkey-confirm",
+        error: "export-privkey-password-error",
+    },
+    {
+        screen: "the recovery phrase screen",
+        open: () => require("../src/popup/views/showPhrase").show(0),
+        field: "show-phrase-password",
+        button: "btn-show-phrase-reveal",
+        error: "show-phrase-password-error",
+    },
+    {
+        screen: "the delete wallet screen",
+        open: () => require("../src/popup/views/deleteWallet").show(0),
+        field: "delete-wallet-password",
+        button: "btn-delete-wallet-confirm",
+        error: "delete-wallet-password-error",
+    },
+])("$screen", ({ open, field, button, error }) => {
+    // Opens the screen and enters a password the vault rejects.
+    async function failedAttempt() {
+        const page = await bootPopup(unversionedValidProfile());
+        open();
+        const { decryptWithPassword } = require("../src/shared/vault");
+        decryptWithPassword.mockRejectedValue(new Error("wrong password"));
+        page.node(field).value = "not the password";
+        await page.click(button);
+        return { page, decryptWithPassword };
+    }
+
+    test("shows a wrong password below the password field", async () => {
+        const { page } = await failedAttempt();
+        expect(errorLine(page, error)).toEqual(shown(WRONG_PASSWORD));
+    });
+
+    test("clears the error while the next password is checked", async () => {
+        const { page, decryptWithPassword } = await failedAttempt();
+        let rejectDecrypt;
+        decryptWithPassword.mockReturnValue(
+            new Promise((resolve, reject) => {
+                rejectDecrypt = reject;
+            }),
+        );
+
+        page.node(field).value = "another guess";
+        const pressed = page.click(button);
+        await page.settle();
+        expect(errorLine(page, error)).toEqual(cleared);
+
+        rejectDecrypt(new Error("wrong password"));
+        await pressed;
+        expect(errorLine(page, error)).toEqual(shown(WRONG_PASSWORD));
+    });
+
+    test("clears the error when the screen is shown again", async () => {
+        const { page } = await failedAttempt();
+        open();
+        expect(errorLine(page, error)).toEqual(cleared);
+    });
+});

tests/persistedFieldContract.test.js

@@ -49,22 +49,37 @@
 // every path a stored record takes, and the difference is the whole of what
 // this file does not cover:
 //
-//   - Only the values in the table, in the SLOT arrangement below: four value
-//     combinations per view, not the product of twelve fields. A dereference
-//     reached only under a pairing no slot produces is not driven at all.
-//   - Only what a stored record reaches by ITSELF. A view only forward
-//     navigation opens, and anything behind a click, is not driven.
-//   - Nothing about the paths a HEALTHY profile takes, which is most of the
-//     popup. This file is a floor under one defect class, not a proof about
-//     the renderers.
+//   - Only the values in the table, in the SLOT arrangement below. On the
+//     restore path the twelve fields the router does not read are corrupted
+//     together, every field on the same slot, so a view gets four value
+//     combinations of them, not their product. A branch entered only when one
+//     of them is truthy and another falsy is reached only where the falsy
+//     slot happens to pair a field that cannot be falsy with one that is.
+//     Each field the router reads is corrupted alone, over an otherwise
+//     well-formed record.
+//   - Only what a stored record reaches by ITSELF, as the boot renders it. A
+//     view only forward navigation opens, anything behind a click, and
+//     anything behind a timer (bootPopup() records every interval, and this
+//     file never runs one) is not driven.
+//   - Of the paths a HEALTHY profile takes, only its boot onto each
+//     restorable view ("the base profile the sweep corrupts" below). The rest
+//     of the popup is not covered: this file is a floor under one defect
+//     class, not a proof about the renderers.
 //
-// Within that boundary it is unconditional: if one of these boots leaves the
-// popup unhealthy or off the view it stored, this file goes red — including
-// when it takes two corrupted fields at once, because the verdict is the
-// combined boot itself and the per-field re-boot below can only decorate the
-// message. That last part is the one thing an earlier version got wrong: it
-// asserted on the per-field list, so an observed dead popup that no single
-// field reproduced was reported green.
+// Within that boundary it is unconditional: if a boot that corrupts a field
+// leaves the popup unhealthy, this file goes red — including when it takes
+// two corrupted fields at once, because the verdict is the combined boot
+// itself and the per-field re-boot below can only decorate the message. That
+// last part is the one thing an earlier version got wrong: it asserted on the
+// per-field list, so an observed dead popup that no single field reproduced
+// was reported green.
+//
+// Where the popup lands is held for some of those boots and not others. The
+// combined boot must land on the view it stored, and each `hostileRestore`
+// value must land on its view, or fall back to Home, as its entry declares.
+// The boots in "a hostile routing value restoring onto" are held to health
+// alone, because a value in a field the router reads legitimately changes
+// which view renders; so are the boots onto Home, which store no view.
 //
 // Booting every field separately at every value would be several hundred boots
 // and most of the suite's budget; this is forty-four. Widening it further is
@@ -128,7 +143,11 @@ const sweptValues = (row) => [...row.hostile, ...(row.falsy || [])];
 // list short and pointed. `floorOnly` is extra values checked against the
 // floor alone, which is pure and free. `hostileRestore` is extra values driven
 // through the restore path only, for a value that means nothing until a
-// particular branch's gate has let it past.
+// particular branch's gate has let it past. Each of its entries names the
+// `views` it is driven onto and declares whether the boot lands on them
+// (`restored: true`) or falls back to Home (`restored: false`), so a value
+// written for one renderer cannot stop reaching it unnoticed. A value driven
+// onto every restorable view is written with everyRestorableView() below.
 //
 // `falsy` is the other POLARITY of a swept field, driven for the same reason.
 // It is not a value src/ never writes — for three of these fields it is the
@@ -139,6 +158,23 @@ const sweptValues = (row) => [...row.hostile, ...(row.falsy || [])];
 // falsy value stored under that field comes back TRUTHY from the floor, so no
 // `!state.x` branch is reachable from a stored record at all.
 
+// The `hostileRestore` entries for a value driven onto every restorable view:
+// it falls back to Home on the views listed in `fallsBackOn` and lands on every
+// other one, so a view added to RESTORABLE_VIEWS is driven, and expected to
+// land, without editing the row.
+function everyRestorableView(value, fallsBackOn) {
+    return [
+        { value, views: fallsBackOn, restored: false },
+        {
+            value,
+            views: [...RESTORABLE_VIEWS].filter(
+                (view) => !fallsBackOn.includes(view),
+            ),
+            restored: true,
+        },
+    ];
+}
+
 const CONTRACT = [
     {
         field: "wallets",
@@ -280,28 +316,38 @@ const CONTRACT = [
         kind: KIND.SCALAR,
         // The prototype members are the whole point: `wallets["map"]` is
         // TRUTHY, so hasValidAddress()'s `&&` does not short-circuit and
-        // `.addresses[…]` throws. A stale INTEGER is the safe case.
-        hostile: ["map", "__proto__", { a: 1 }],
+        // `.addresses[…]` throws. A stale INTEGER is the safe case and has to
+        // stay so. 5 is one, out of range for the one wallet in the profile,
+        // and it is also this field's truthy polarity: every other value here
+        // comes back from the floor as null.
+        hostile: ["map", "__proto__", { a: 1 }, 5],
         floorOnly: ["length", "constructor", "toString", "0", -1, 1.5, true],
         holds: isIndexOrNull,
         // SCALAR, and swept anyway: the restore path is precisely why this
         // field gained a floor, so the sweep is the regression guard on it.
         alsoSweep: true,
         routes: true,
-        // A stale INTEGER index, which reaches the restore path by a different
-        // route from the prototype members above — falsy or out of range
-        // rather than truthy — and has to keep being the safe case.
-        hostileRestore: [{ value: "length" }, { value: 5 }],
+        // Comes back from the floor as null, which hasValidAddress() reads as
+        // nothing selected: the popup falls back to Home on the five views
+        // that need an address, and lands on every other one.
+        hostileRestore: everyRestorableView("length", [
+            "address",
+            "address-token",
+            "receive",
+            "transaction",
+            "confirm-tx",
+        ]),
     },
     {
         field: "selectedAddress",
         kind: KIND.SCALAR,
-        hostile: ["map", "__proto__", { a: 1 }],
+        // 5 for the same reason as in selectedWallet: a stale index, and the
+        // one value here still truthy after the floor.
+        hostile: ["map", "__proto__", { a: 1 }, 5],
         floorOnly: ["length", "constructor", "toString", "0", -1, 1.5, true],
         holds: isIndexOrNull,
         alsoSweep: true,
         routes: true,
-        hostileRestore: [{ value: 5 }],
     },
     {
         field: "currentView",
@@ -325,7 +371,9 @@ const CONTRACT = [
         // container shapes below onto every restorable view; hostileRestore
         // adds the records that PASS a branch's gate and then hand its
         // renderer something it dereferences, which is where the entries are
-        // actually decided.
+        // actually decided. The guard refuses each single-view record below,
+        // so each is declared to fall back to Home: one that started landing
+        // would be reaching the renderer it was written against.
         hostile: [42, "notarecord", { a: 1 }, [1, 2]],
         // `structuredClone(saved.viewData || {})`: the container is never falsy
         // in state whatever was stored, so no `!state.viewData` branch exists to
@@ -334,11 +382,20 @@ const CONTRACT = [
         hostileRestore: [
             // success-tx passes on `data.hash`, and renderSuccess() then calls
             // toAddressHtml(d.to) -> addressTitle() -> address.toLowerCase().
-            { value: { hash: "0x1" }, views: ["success-tx"] },
-            { value: { hash: "0x1", to: 42 }, views: ["success-tx"] },
+            {
+                value: { hash: "0x1" },
+                views: ["success-tx"],
+                restored: false,
+            },
+            {
+                value: { hash: "0x1", to: 42 },
+                views: ["success-tx"],
+                restored: false,
+            },
             {
                 value: { hash: "0x1", to: ADDRESS, decoded: { details: 7 } },
                 views: ["success-tx"],
+                restored: false,
             },
             {
                 value: {
@@ -347,12 +404,25 @@ const CONTRACT = [
                     decoded: { details: [{ address: 42 }] },
                 },
                 views: ["success-tx"],
+                restored: false,
             },
             // error-tx passes on `data.message`, same dereference.
-            { value: { message: "boom" }, views: ["error-tx"] },
-            { value: { message: "boom", to: 42 }, views: ["error-tx"] },
+            {
+                value: { message: "boom" },
+                views: ["error-tx"],
+                restored: false,
+            },
+            {
+                value: { message: "boom", to: 42 },
+                views: ["error-tx"],
+                restored: false,
+            },
             // transaction passes on `data.tx`.
-            { value: { tx: { hash: "0x1" } }, views: ["transaction"] },
+            {
+                value: { tx: { hash: "0x1" } },
+                views: ["transaction"],
+                restored: false,
+            },
             {
                 value: {
                     tx: {
@@ -363,9 +433,14 @@ const CONTRACT = [
                     },
                 },
                 views: ["transaction"],
+                restored: false,
             },
             // confirm-tx passes on `data.pendingTx`.
-            { value: { pendingTx: { amount: "1" } }, views: ["confirm-tx"] },
+            {
+                value: { pendingTx: { amount: "1" } },
+                views: ["confirm-tx"],
+                restored: false,
+            },
             {
                 value: {
                     pendingTx: {
@@ -376,6 +451,7 @@ const CONTRACT = [
                     },
                 },
                 views: ["confirm-tx"],
+                restored: false,
             },
             // wait-tx passes on `pendingWait.hash`; restoreWait() has checked
             // the fields below it since it was written, and this is the
@@ -388,20 +464,29 @@ const CONTRACT = [
                     },
                 },
                 views: ["wait-tx"],
+                restored: false,
             },
             // A record that passes EVERY branch's gate at once, driven onto
             // every restorable view: a branch a view does not read must stay
-            // one it does not read, and each renderer must survive the fields
-            // another branch left behind.
-            {
-                value: {
+            // one it does not read. The five views with a viewData branch
+            // refuse it; every other one renders it, and must survive the
+            // fields every branch left behind.
+            ...everyRestorableView(
+                {
                     hash: "0x1",
                     message: "boom",
                     tx: { hash: "0x1" },
                     pendingTx: { amount: "1" },
                     pendingWait: { hash: "0x1" },
                 },
-            },
+                [
+                    "confirm-tx",
+                    "transaction",
+                    "wait-tx",
+                    "success-tx",
+                    "error-tx",
+                ],
+            ),
         ],
     },
     {
@@ -583,6 +668,11 @@ const HEALTHY = { errors: [], blank: false };
 // set is all-truthy by construction, so without a falsy slot a dereference
 // behind `if (!state.x)` is never reached on the boot that corrupts x — the
 // same falsy-collapse blind spot the fields below were floored for.
+//
+// Only `hostile` and `falsy` values count. Those go through the sweep below,
+// which covers every restorable view; a `hostileRestore` entry is driven onto
+// only the views it names, so a polarity it alone supplied might reach a single
+// renderer.
 describe("both polarities of every swept field are driven", () => {
     const FALSY_STORED = [0, "", false, null];
     const floored = (field, value) =>
@@ -606,10 +696,9 @@ describe("both polarities of every swept field are driven", () => {
         test(`${row.field}: truthy and falsy`, () => {
             // What the boots below actually drive, floored the way a renderer
             // sees it — not what the row says it drives.
-            const driven = [
-                ...sweptValues(row),
-                ...(row.hostileRestore || []).map((entry) => entry.value),
-            ].map((value) => floored(row.field, value));
+            const driven = sweptValues(row).map((value) =>
+                floored(row.field, value),
+            );
 
             expect({
                 truthy: driven.some((value) => Boolean(value)),
@@ -865,20 +954,27 @@ describe("every field the router does not read, corrupted at once, onto", () =>
 
 // The values that only mean something on the restore path: a viewData that
 // PASSES a branch's gate and then hands its renderer something dereferenced,
-// and the index values whose route through hasValidAddress() differs from the
-// row's own hostile set.
+// and a selectedWallet the floor turns into nothing selected. Each boot must
+// throw nothing and show exactly the view its entry says it lands on: its own,
+// or Home, so a value written for one renderer cannot stop reaching it and
+// still pass.
 describe("a restore-only hostile value onto", () => {
     for (const row of CONTRACT) {
         for (const entry of row.hostileRestore || []) {
-            for (const view of entry.views || RESTORABLE_VIEWS) {
+            for (const view of entry.views) {
                 test(`${view}: ${row.field} = ${JSON.stringify(
                     entry.value,
                 )}`, async () => {
-                    await expect(
-                        bootHealth(
-                            restoringOnto(view, { [row.field]: entry.value }),
-                        ),
-                    ).resolves.toEqual(HEALTHY);
+                    const env = await bootPopup(
+                        restoringOnto(view, { [row.field]: entry.value }),
+                    );
+                    expect({
+                        errors: env.pageErrors,
+                        visible: env.visibleViews(),
+                    }).toEqual({
+                        errors: [],
+                        visible: [entry.restored ? view : "main"],
+                    });
                 });
             }
         }

tests/showPhrase.test.js

@@ -131,8 +131,10 @@ describe("Back from Settings after leaving by the settings gear", () => {
 
     // https://git.eeqj.de/sneak/AutistMask/issues/461: leaving drops the
     // wallet selection, so Back onto this screen showed a password prompt
-    // that could only answer "No wallet is selected."
-    test("does not land on the recovery phrase screen", () => {
+    // that could only answer "No wallet is selected." Taking the screen off
+    // the stack leaves Settings under Settings, and Back must not land there
+    // either (https://git.eeqj.de/sneak/AutistMask/issues/481).
+    test("goes to the screen under Settings", () => {
         const { helpers, state, showPhrase } = load();
 
         // Opened from the wallet list in Settings, then left by the gear:
@@ -143,7 +145,21 @@ describe("Back from Settings after leaving by the settings gear", () => {
 
         expect(state.viewStack).toEqual(["main", "settings"]);
         helpers.goBack();
-        expect(state.currentView).not.toBe(SHOW_PHRASE_VIEW);
+        expect(state.currentView).toBe("main");
+    });
+
+    // Each round trip leaves one more Settings under Settings.
+    test("goes to the screen under Settings after two round trips", () => {
+        const { helpers, state, showPhrase } = load();
+        for (let i = 0; i < 2; i++) {
+            showPhrase.show(0);
+            helpers.pushCurrentView();
+            helpers.showView("settings");
+        }
+
+        expect(state.viewStack).toEqual(["main", "settings", "settings"]);
+        helpers.goBack();
+        expect(state.currentView).toBe("main");
     });
 
     // This Back takes Settings off the stack before the screen is left, so