fix: each browser-suite run builds and removes an image of its own (closes #547)

script/test-e2e and script/test-e2e-firefox tagged their image with one
fixed name. When two clones ran a suite at once, the second build moved
that tag, the image store deleted the first run's now-untagged image, and
that suite exited 125 without running a test. Each run now tags its image
with the suite's name and twelve random hex digits, runs it by that tag,
and removes it in the scripts' existing exit and interrupt cleanup, so no
run leaves an image behind. The image-ID file that guarded against a
moving tag is no longer needed. README.md's End-to-End Tests section says
so.

Model: opus-5-5

README.md

@@ -239,8 +239,12 @@ provide:
   `make check` stays non-mutating. Linting runs only in the container, because
   an ESLint result that depends on whichever ESLint the host happens to have is
   not a result, so docker is required to lint.
-- `script/fmt` — format all files (writes), on the host
-- `script/fmt-check` — check formatting (read-only), on the host
+- `script/fmt` — format all files (writes), on the host, with the `prettier`
+  that `script/bootstrap` installs in `node_modules/`; when that one is missing
+  it fails and says to run `script/bootstrap`, instead of using a `prettier`
+  from the `PATH`
+- `script/fmt-check` — check formatting (read-only), on the host, with the same
+  `prettier` and the same refusal
 - `script/check` — run `script/test`, `script/lint` and `script/fmt-check`
 - `script/check-censored` — assert the competitor name RULES.md bars appears
   nowhere in the working tree or under `dist/` outside its documented
@@ -343,6 +347,12 @@ 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.
 
+Each run builds its image under a tag of its own, `autistmask-e2e-chrome:` or
+`autistmask-e2e-firefox:` followed by twelve random hex digits, and removes that
+image when it exits, an interrupt included. Two clones can therefore run the
+same suite at once without one build taking the other's image away, and no run
+leaves an image behind.
+
 ### Chrome (`make test-e2e`)
 
 `make test-e2e` builds `dist/chrome/` and drives the **real popup in a real
@@ -422,11 +432,12 @@ 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
+network switch in Settings is required to send the page `chainChanged` with the
+new chain id, 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).
 
 The limits of that coverage and of the rest of the Chrome suite, none of them
@@ -1785,10 +1796,12 @@ view would leave a wallet one click from deletion.
       plus a "+ Add token" button
     - 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. The
+    - Network: network selector (Ethereum Mainnet / Sepolia Testnet). The
       network changes only here, or when the user approves a site's request on
-      **NetworkApproval**
+      **NetworkApproval**; either way, switching restores the RPC and Blockscout
+      endpoints last used on that network, or that network's defaults if it has
+      none, and sends `chainChanged` with the new chain id to every open tab.
+      Choosing the network already active changes nothing and sends nothing
     - Ethereum RPC: endpoint URL input + "Save" button (validated against
       `eth_chainId` before being saved)
     - Blockscout API: endpoint URL input + "Save" button (validated against
@@ -2157,6 +2170,13 @@ view would leave a wallet one click from deletion.
     - Typed data that states no primary type, or one other than the type it
       would be signed as, or that cannot be read → shown with the error line
       saying so and "Sign" disabled; only "Reject" remains
+    - Typed data whose domain `chainId` names a chain other than the active
+      network's → shown with the error line naming both chain ids and "Sign"
+      disabled; only "Reject" remains. EIP-712 asks for this, because the
+      signature is valid on the chain the domain names. Typed data with no
+      `chainId` is not refused. The background refuses such a signature too,
+      against the network active when the signature reaches it, and answers the
+      site with the same sentence
     - A `personal_sign` or `eth_sign` message that is not hex (`0x` or `0X` and
       an even number of hex digits, the form ethers' `getBytes` reads when
       signing) → shown as plain text, with the error line "This message is plain
@@ -2197,8 +2217,9 @@ view would leave a wallet one click from deletion.
     - "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
+      **Settings** does, restoring the RPC and Blockscout endpoints last used on
+      that network (or that network's defaults if it has none), 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"
@@ -2648,7 +2669,8 @@ plaintext list of anyone's domain names.
 When a dApp on a blocklisted domain requests a wallet connection, transaction
 approval, or signature, the approval popup displays a prominent red warning
 banner alerting the user. The domain checker matches exact hostnames and all
-parent domains (subdomain matching).
+parent domains (subdomain matching), and checks a hostname written with a
+trailing dot (`name.`) as `name`.
 
 #### Transaction Decoding
 
@@ -2691,7 +2713,7 @@ Currently supported:
 
 ### Non-Goals for 1.0
 
-- Multi-chain support (Ethereum mainnet only)
+- Chains other than Ethereum mainnet and the Sepolia testnet
 - Hardware wallet support
 
 ## TODO
@@ -2725,7 +2747,10 @@ Currently supported:
 ## Policies
 
 - We don't mention "the other wallet" by name in code or documentation. We're
-  our own thing.
+  our own thing. Written exception: the injected provider in
+  `src/content/inpage.js` sets the flag named after the other wallet to `true`.
+  It is an interface-compatibility flag many dApps check, and without it the
+  wallet stops working on their sites.
 - The README is the complete authoritative technical documentation. It's ok if
   it gets big.
 

RULES.md

@@ -118,4 +118,7 @@ contradicts either, the originals govern.
 - [ ] "Address" not "account" or "derived key"
 - [ ] "Password" not "encryption key" or "vault passphrase"
 - [ ] Error messages are full sentences
-- [ ] No competitor mentioned by name in code or documentation
+- [ ] No competitor mentioned by name in code or documentation. Written
+      exception: the injected provider in `src/content/inpage.js` sets the flag
+      named after the other wallet to `true`, an interface-compatibility flag
+      many dApps check (README.md, Policies)

TODO.md

@@ -2,10 +2,9 @@
 
 - `git pull` `next` and cut a branch from it — one branch per issue, named
   `issue-<N>-<slug>`. Never branch from `main`.
-- Do the work as one commit whose title ends with ` (closes #N)`, with the
-  `TODO.md` update in that same commit.
-- Move Next Step to the top of Completed Steps; move the top item of Future
-  Steps into Next Step.
+- Do the work as one commit whose title ends with ` (closes #N)`.
+- Add no entry to Completed Steps. What landed is recorded on the tracker and in
+  `git log`, where each commit title names the issue it closes.
 - Run `make fmt`, then `make check`. A feature branch may be red; `next` and
   `main` may not.
 - Rebase onto current `next` immediately before pushing — other branches land on
@@ -44,6 +43,25 @@ then continue tagging as milestones land.
 
 # Completed Steps
 
+- 2026-10-08: The browser suites no longer read a screen before the page has
+  shown it ([#502](https://git.eeqj.de/sneak/AutistMask/issues/502)). Their wait
+  for a screen used to pass as soon as the element laid out, which every view
+  does until the page's stylesheet has applied, so an approval test could read
+  the prompt's fields before the page's script had filled them. `visible()` in
+  `tests/e2e/harness.js` and `waitVisible()` in `tests/e2e/firefox/driver.js`
+  now also wait for the page to finish loading and for neither the element nor
+  anything around it to carry the `hidden` class that `showView()` puts on every
+  view but the current one. No caller changed.
+
+- 2026-10-08: Switching the network in Settings now tells open pages
+  ([#500](https://git.eeqj.de/sneak/AutistMask/issues/500)). Once the switch is
+  saved, Settings asks the background to send `chainChanged` with the new chain
+  id to every open tab, through the same function an approved site request uses.
+  Choosing the network already active changes nothing and sends nothing. Only
+  the extension's own pages can ask for this. `tests/chainSwitchGate.test.js`
+  drives the real Settings view against the background, and the Chrome suite
+  checks that the test page hears both switches.
+
 - 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
@@ -54,9 +72,20 @@ then continue tagging as milestones land.
   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
+  the same port as the new one; `tests/approvalWindow.test.js` checks that it
+  shows no screen until then. `tests/chainSwitchGate.test.js` and both browser
   suites drive the prompt.
 
+- 2026-10-07: Two contradictions between the documents and the code are resolved
+  as ruled on [#165](https://git.eeqj.de/sneak/AutistMask/issues/165). The
+  README's 1.0 non-goal now puts Ethereum mainnet and the Sepolia testnet in
+  scope and other chains out of it. The injected provider's flag named after the
+  other wallet stays, as an interface-compatibility flag many dApps check, and
+  is written down as an exception to the rule against naming competitors in the
+  README's Policies section, in `RULES.md` and in a comment beside it in
+  `src/content/inpage.js`. `script/check-censored` already allows that flag only
+  in that file and its built copies, so it is unchanged.
+
 - 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

script/fmt

@@ -25,6 +25,13 @@ run_yarn() {
 
 main() {
     cd "$ROOT"
+    # Without the repo's own prettier, yarn runs whatever prettier is on
+    # the PATH, which may be a version that formats files differently.
+    if [ ! -x node_modules/.bin/prettier ]; then
+        echo "fmt: this repo's prettier is not installed in node_modules/," \
+            "so run script/bootstrap first." >&2
+        exit 1
+    fi
     echo "Formatting..."
     run_yarn run fmt
 }

script/fmt-check

@@ -26,6 +26,13 @@ run_yarn() {
 
 main() {
     cd "$ROOT"
+    # Without the repo's own prettier, yarn runs whatever prettier is on
+    # the PATH, which may be a version that formats files differently.
+    if [ ! -x node_modules/.bin/prettier ]; then
+        echo "fmt-check: this repo's prettier is not installed in" \
+            "node_modules/, so run script/bootstrap first." >&2
+        exit 1
+    fi
     echo "Checking formatting..."
     run_yarn run fmt-check
 }

script/test-e2e

@@ -22,13 +22,18 @@ set -eu
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
 ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
 
-IMAGE="$("$SCRIPT_DIR/projectname")-e2e-chrome"
-
-IIDFILE=""
+# Each run builds, runs and then removes an image under a tag of its own.
+# Under one tag shared by every run, a second clone's build moves the tag
+# off this run's image, and the image store can then delete that untagged
+# image before or while this run uses it. The tag is random rather than
+# $$ because CI jobs share one docker daemon, but each job's container
+# numbers its processes from scratch.
+IMAGE="$("$SCRIPT_DIR/projectname")-e2e-chrome:$(od -An -N6 -tx1 /dev/urandom | tr -d ' \n')"
 
 cleanup() {
-    if [ -n "$IIDFILE" ]; then
-        rm -f "$IIDFILE"
+    # No image to remove when the build failed or was interrupted.
+    if docker image inspect "$IMAGE" >/dev/null 2>&1; then
+        docker image rm "$IMAGE" >/dev/null
     fi
 }
 
@@ -40,22 +45,15 @@ main() {
         exit 1
     fi
 
-    IIDFILE="$(mktemp)"
     trap cleanup EXIT
     trap 'cleanup; exit 130' INT TERM
 
     echo "Building the Chrome e2e image (extension included)..."
     # --no-cache: the image build runs make build and its checks, and a
     # cached layer is a check that did not run.
-    docker build --no-cache --iidfile "$IIDFILE" -t "$IMAGE" \
-        -f tests/e2e/Dockerfile .
+    docker build --no-cache -t "$IMAGE" -f tests/e2e/Dockerfile .
 
     echo "Running e2e suite in the pinned Playwright container..."
-    # The image is run by ID, not by tag: where two clones of this repo run
-    # the suite at once, the other build can move the tag between this
-    # build and this run, and the suite would then silently test the other
-    # checkout.
-    #
     # --ipc=host: Chromium's shared-memory needs more than the default
     #   64MB /dev/shm or renderers crash.
     # HOME=/tmp: the image's root home is not a reliable place for the
@@ -79,7 +77,7 @@ main() {
         -e HOME=/tmp \
         -e PW_EXPERIMENTAL_SERVICE_WORKER_NETWORK_EVENTS=1 \
         -e "E2E_TRACE_NETWORK=${E2E_TRACE_NETWORK:-0}" \
-        "$(cat "$IIDFILE")" \
+        "$IMAGE" \
         node tests/e2e/run.js
 
     # Where chrome.storage.local lives, and what moves it: two unpacked loads
@@ -95,7 +93,7 @@ main() {
     docker run --rm \
         --ipc=host \
         -e HOME=/tmp \
-        "$(cat "$IIDFILE")" \
+        "$IMAGE" \
         node tests/e2e/storagePartition.js
 }
 

script/test-e2e-firefox

@@ -21,13 +21,13 @@ set -eu
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
 ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
 
-IMAGE="$("$SCRIPT_DIR/projectname")-e2e-firefox"
-
-IIDFILE=""
+# A tag of this run's own, as in script/test-e2e, which says why.
+IMAGE="$("$SCRIPT_DIR/projectname")-e2e-firefox:$(od -An -N6 -tx1 /dev/urandom | tr -d ' \n')"
 
 cleanup() {
-    if [ -n "$IIDFILE" ]; then
-        rm -f "$IIDFILE"
+    # No image to remove when the build failed or was interrupted.
+    if docker image inspect "$IMAGE" >/dev/null 2>&1; then
+        docker image rm "$IMAGE" >/dev/null
     fi
 }
 
@@ -39,22 +39,15 @@ main() {
         exit 1
     fi
 
-    IIDFILE="$(mktemp)"
     trap cleanup EXIT
     trap 'cleanup; exit 130' INT TERM
 
     echo "Building the pinned Firefox e2e image (extension included)..."
     # --no-cache: the image build runs make build and its checks, and a
     # cached layer is a check that did not run.
-    docker build --no-cache --iidfile "$IIDFILE" -t "$IMAGE" \
-        -f tests/e2e/firefox/Dockerfile .
+    docker build --no-cache -t "$IMAGE" -f tests/e2e/firefox/Dockerfile .
 
     echo "Running the Firefox e2e suite..."
-    # The image is run by ID, not by tag: where two clones of this repo run
-    # the suite at once, the other build can move the tag between this
-    # build and this run, and the suite would then silently test the other
-    # checkout.
-    #
     # --shm-size=1g: Firefox needs more than the default 64MB /dev/shm.
     # --network none: the suite stubs nothing, so this is what keeps the
     #   run offline and deterministic. The extension swallows its own
@@ -72,7 +65,7 @@ main() {
         --shm-size=1g \
         --network none \
         -e HOME=/tmp \
-        "$(cat "$IIDFILE")" \
+        "$IMAGE" \
         node tests/e2e/firefox/run.js dist/firefox
 
     # The install/uninstall/re-install property, against the packaged XPI
@@ -85,7 +78,7 @@ main() {
         --shm-size=1g \
         --network none \
         -e HOME=/tmp \
-        "$(cat "$IIDFILE")" \
+        "$IMAGE" \
         node tests/e2e/firefox/reinstall.js
 }
 

src/background/index.js

@@ -22,6 +22,7 @@ const { debugFetch, log } = require("../shared/log");
 const {
     verifySignedTx,
     verifySignature,
+    typedDataChainRefusal,
     failureIsRetryable,
     describeTxFailure,
     sameAddress,
@@ -632,8 +633,9 @@ function isExtensionSender(sender) {
 // had refused.
 //
 // TX and sign approvals do not decide here. They stay pending across a
-// disconnect — the user can reopen the toolbar popup — and are rejected by the
-// windows.onRemoved listener below.
+// disconnect. When their window closes, the windows.onRemoved listener below
+// rejects them, unless an approved attempt is still running, in which case
+// that attempt answers the page.
 runtime.onConnect.addListener((port) => {
     if (port.name.startsWith("approval:")) {
         const id = port.name.split(":")[1];
@@ -661,7 +663,9 @@ runtime.onConnect.addListener((port) => {
             const approval = pendingApprovals[id];
             if (approval) {
                 if (approval.type === "tx" || approval.type === "sign") {
-                    // Keep pending — user can reopen the toolbar popup
+                    // When its window closes, windows.onRemoved rejects it,
+                    // unless an approved attempt is still running, in which
+                    // case that attempt answers the page.
                     return;
                 }
                 settleApproval(id, { approved: false, remember: false });
@@ -1471,6 +1475,7 @@ runtime.onMessage.addListener((msg, sender, sendResponse) => {
         "AUTISTMASK_ADDRESSES_REMOVED",
         "AUTISTMASK_GET_CONNECTED_SITES",
         "AUTISTMASK_REMOVE_SITE",
+        "AUTISTMASK_NETWORK_CHANGED",
     ];
     if (POPUP_ONLY_TYPES.includes(msg.type) && !isExtensionSender(sender)) {
         sendResponse({ error: "Unauthorized sender" });
@@ -1763,7 +1768,8 @@ runtime.onMessage.addListener((msg, sender, sendResponse) => {
 
         (async () => {
             try {
-                const activeAddress = await getActiveAddress();
+                const s = await getState();
+                const activeAddress = activeAddressOf(s);
                 // Same as the transaction path: the address the approval named
                 // is the one that must have signed, and a switch since then is
                 // a refusal rather than a signature from another account.
@@ -1782,6 +1788,20 @@ runtime.onMessage.addListener((msg, sender, sendResponse) => {
                     signature,
                     approval.approvedFrom,
                 );
+                // The sign screen refuses typed data whose domain names
+                // another chain. A signature for it that arrives anyway is
+                // refused here, against the network active now.
+                const sp = approval.signParams;
+                if (
+                    sp.method === "eth_signTypedData_v4" ||
+                    sp.method === "eth_signTypedData"
+                ) {
+                    const refusal = typedDataChainRefusal(
+                        JSON.parse(sp.typedData).domain,
+                        networkById(s.networkId),
+                    );
+                    if (refusal) throw new ApprovalMismatchError(refusal);
+                }
                 settleApproval(msg.id, { signature }, { holdsClaim: true });
                 sendResponse({ signature });
             } catch (e) {
@@ -1854,6 +1874,13 @@ runtime.onMessage.addListener((msg, sender, sendResponse) => {
         broadcastSiteRemoved(msg.origin);
         return false;
     }
+
+    // Settings switched the network and has saved it. Open tabs are told the
+    // new chain id the same way as after a site's approved switch request.
+    if (msg.type === "AUTISTMASK_NETWORK_CHANGED") {
+        broadcastChainChanged(msg.chainId);
+        return false;
+    }
 });
 
 module.exports = { PROXY_METHODS };

src/content/inpage.js

@@ -99,7 +99,10 @@
 
     const provider = {
         isAutistMask: true,
-        isMetaMask: true, // compatibility — many dApps check this
+        // An interface-compatibility flag many dApps check. Kept as a written
+        // exception to the rule that no competitor is named in code: see
+        // Policies in README.md, and RULES.md.
+        isMetaMask: true,
         chainId: currentChainId,
         networkVersion: currentNetworkVersion,
         selectedAddress: null,

src/popup/index.html

@@ -7,9 +7,10 @@
         <link rel="stylesheet" href="styles.css" />
     </head>
     <!-- Chrome gives extension pages a stylesheet of its own that sets the
-         font on body, and a Tailwind class beats it only when marked
-         important: hence font-mono! rather than font-mono. -->
-    <body class="bg-bg text-fg font-mono! text-sm">
+         font and its size on body, and a Tailwind class beats it only when
+         marked important: hence font-mono! and text-sm! rather than
+         font-mono and text-sm. -->
+    <body class="bg-bg text-fg font-mono! text-sm!">
         <div id="app" class="p-2 pr-5 overflow-x-hidden">
             <!-- ============ GLOBAL TITLE BAR ============ -->
             <div
@@ -87,11 +88,14 @@
 
                 <!-- Mnemonic form section -->
                 <div id="add-wallet-section-mnemonic">
-                    <p class="mb-2">
-                        Enter your 12 or 24 word recovery phrase below, or click
-                        the button to roll the die for a new one.
-                    </p>
-                    <div class="mb-1 flex justify-end">
+                    <!-- The die button shares the instruction's row: on a row
+                         of its own it pushes Import below the fold at
+                         360x600. -->
+                    <div class="mb-2 flex justify-between items-start gap-2">
+                        <p>
+                            Enter your 12 or 24 word recovery phrase below, or
+                            click the button to roll the die for a new one.
+                        </p>
                         <button
                             id="btn-generate-phrase"
                             class="border border-border px-2 py-1 hover:bg-fg hover:text-bg cursor-pointer text-xs"

src/popup/views/approval.js

@@ -12,7 +12,7 @@ const {
     formatFee,
     tokenLabel,
 } = require("./helpers");
-const { state, saveState } = require("../../shared/state");
+const { state, saveState, currentNetwork } = require("../../shared/state");
 const {
     networkById,
     networkByChainId,
@@ -46,7 +46,10 @@ const {
 const { decryptWithPassword } = require("../../shared/vault");
 const { getSignerForAddress } = require("../../shared/wallet");
 const { walletDefect } = require("../../shared/walletDefects");
-const { describeSigningFailure } = require("../../shared/approvalVerify");
+const {
+    describeSigningFailure,
+    typedDataChainRefusal,
+} = require("../../shared/approvalVerify");
 const txStatus = require("./txStatus");
 const uniswap = require("../../shared/uniswap");
 const { notify, runtimeApi, sendMessage } = require("../../shared/browserApi");
@@ -329,9 +332,9 @@ function showTxApproval(details) {
     const ethUsd = ethPrice ? parseFloat(ethValueFormatted) * ethPrice : null;
     const usdStr = formatUsd(ethUsd);
     // In the native currency of the network the transaction is for, which the
-    // Network line names, not the active network's: a site can switch the
-    // active network after this transaction is prepared and back before it is
-    // signed.
+    // Network line names, not the active network's: the active network can
+    // change, in Settings or when the user approves a site's request, after
+    // this transaction is prepared and change back before it is signed.
     $("approve-tx-value").textContent =
         ethValueFormatted +
         " " +
@@ -443,7 +446,8 @@ function signedPrimaryType(types) {
 // Why a signature request cannot be signed, as a sentence for the error line,
 // or null when it can. Only typed data is refused: the `primaryType` the page
 // states has to be the type ethers will sign, or this screen would name one
-// message while another is signed.
+// message while another is signed. Its domain may name no chain but the active
+// network's.
 function typedDataRefusal(sp) {
     if (sp.method === "personal_sign" || sp.method === "eth_sign") return null;
     let data;
@@ -466,7 +470,7 @@ function typedDataRefusal(sp) {
             ", so it cannot be signed."
         );
     }
-    return null;
+    return typedDataChainRefusal(data.domain, currentNetwork());
 }
 
 // The largest amount a Permit2 allowance can hold, a uint160. Permit2 treats

src/popup/views/settings.js

@@ -316,7 +316,11 @@ function init(ctx) {
     const networkSelect = $("settings-network");
     networkSelect.addEventListener("change", async () => {
         const newId = networkSelect.value;
+        if (newId === state.networkId) return;
         const net = await onChainSwitch(newId);
+        // Open pages are told by the background, as after a site's approved
+        // switch request.
+        notify({ type: "AUTISTMASK_NETWORK_CHANGED", chainId: net.chainId });
         $("settings-rpc").value = state.rpcUrl;
         $("settings-blockscout").value = state.blockscoutUrl;
         showFlash("Switched to " + net.name + ".");

src/popup/views/transactionDetail.js

@@ -84,8 +84,9 @@ function show(tx) {
             contractAddress: tx.contractAddress || null,
             // The network the history entry was read from. The type line and
             // the fee are in its native currency, not the active network's:
-            // a site can switch the active network before a later popup
-            // shows this screen again.
+            // the active network can change, in Settings or when the user
+            // approves a site's request, before a later popup shows this
+            // screen again.
             chainId: tx.chainId,
         },
     };

src/popup/views/txStatus.js

@@ -89,8 +89,9 @@ function startWait(txInfo, txHash, broadcastTime, pollNow) {
 
     // A native amount, here and on the success and error screens, is in the
     // native currency of txInfo.chainId, the network the transaction was sent
-    // on, not the active network's: a site can switch the active network
-    // while this screen is open or before a later popup resumes it.
+    // on, not the active network's: the active network can change, in
+    // Settings or when the user approves a site's request, while this screen
+    // is open or before a later popup resumes it.
     const symbol =
         txInfo.token === "ETH"
             ? nativeCurrencyByChainId(txInfo.chainId)

src/shared/approvalVerify.js

@@ -53,6 +53,7 @@ const {
     accessListify,
     formatEther,
     getAddress,
+    getBigInt,
     getBytes,
     toQuantity,
     verifyMessage,
@@ -635,6 +636,33 @@ function verifySignature(signParams, signature, expectedFrom) {
     return recovered;
 }
 
+// Why typed data cannot be signed while `network` is the active network, as a
+// sentence, or null when it can. EIP-712 has a wallet refuse typed data whose
+// domain names another chain, because the signature is valid on that chain.
+// ethers signs no chain id when the domain's is null or absent, and reads any
+// other with getBigInt(), so 1, "1" and "0x1" are the same chain here too.
+function typedDataChainRefusal(domain, network) {
+    const chainId = domain?.chainId;
+    if (chainId === undefined || chainId === null) return null;
+    let named;
+    try {
+        named = getBigInt(chainId);
+    } catch {
+        return "This typed data cannot be read, so it cannot be signed.";
+    }
+    const active = getBigInt(network.chainId);
+    if (named === active) return null;
+    return (
+        "This typed data is for chain id " +
+        named +
+        ", but the active network is " +
+        network.name +
+        " (chain id " +
+        active +
+        "), so it cannot be signed."
+    );
+}
+
 // The stage a transaction approval failed at. Which stage it is decides
 // whether the approval survives the failure.
 const TX_STAGE_SIGN = "sign";
@@ -796,6 +824,7 @@ function describeSigningFailure(response, fallbackMessage) {
 module.exports = {
     verifySignedTx,
     verifySignature,
+    typedDataChainRefusal,
     assertNoForbiddenFields,
     assertNothingUnchecked,
     assertCanonicalBytes,

src/shared/phishingDomains.js

@@ -110,11 +110,14 @@ function hashListed(hash) {
  * Generate hostname variants for subdomain matching.
  * "sub.evil.com" yields ["sub.evil.com", "evil.com"].
  *
+ * A trailing dot is dropped: "evil.com." is the fully qualified spelling of
+ * "evil.com", and the browser loads the same site from either.
+ *
  * @param {string} hostname
  * @returns {string[]}
  */
 function hostnameVariants(hostname) {
-    const h = hostname.toLowerCase();
+    const h = hostname.toLowerCase().replace(/\.$/, "");
     const variants = [h];
     const parts = h.split(".");
     // Parent domains: a.b.c.d -> b.c.d, c.d

src/shared/walletDefects.js

@@ -36,11 +36,13 @@ const DEFECTS = {
                 "derivation path beneath that key instead of from a master " +
                 "key, so the addresses listed here are not the ones that key " +
                 "produces under the standard path.",
-            "Signing and sending are disabled for this wallet. The addresses " +
-                "do descend from the extended private key you imported, so " +
-                "anything they hold is still reachable by software that " +
-                "repeats the same non-standard derivation. Check them in a " +
-                "block explorer before deciding what to do.",
+            "Signing, sending and private key export are disabled for this " +
+                "wallet. Anything these addresses hold can be reached outside " +
+                "this wallet with the extended private key you imported, if " +
+                "you kept a copy of it, or with the master extended private " +
+                "key or recovery phrase it came from, in software that " +
+                "repeats the same non-standard derivation. Check the " +
+                "addresses in a block explorer before deciding what to do.",
             "To see the addresses this key produces under the standard path, " +
                 "import the master extended private key, or the recovery " +
                 "phrase it came from, as a new wallet. Nothing here has been " +

tests/approvalWindow.test.js

@@ -0,0 +1,47 @@
+// The approval window shows no screen until the background has described the
+// approval it answers (https://git.eeqj.de/sneak/AutistMask/issues/408). The
+// connection prompt's "Allow" and the network switch prompt's "Switch" answer
+// on the same port, so a window that showed the connection prompt while it
+// waited could approve a network switch.
+//
+// Booted through the real popup entry point, which is where the connection
+// prompt used to be put up before the background had answered.
+
+const {
+    bootPopup,
+    cleanupPopup,
+    settle,
+    unversionedValidProfile,
+} = require("./support/popupBoot");
+
+afterEach(cleanupPopup);
+
+test("the approval window shows no screen until the background describes the approval", async () => {
+    // The background's answer, held until the test gives it.
+    let answer = null;
+    const env = await bootPopup(unversionedValidProfile(), {
+        search: "?approval=approval-1",
+        runtime: {
+            connect: () => ({ postMessage: () => {} }),
+            sendMessage: (msg, reply) => {
+                if (msg.type === "AUTISTMASK_GET_APPROVAL") answer = reply;
+            },
+        },
+    });
+
+    expect(answer).not.toBeNull();
+    // No screen at all, the connection prompt included.
+    expect(env.visibleViews()).toEqual([]);
+
+    answer({
+        type: "network",
+        origin: "https://dapp.example",
+        currentNetworkId: "mainnet",
+        requestedNetworkId: "sepolia",
+        isPhishingDomain: false,
+    });
+    await settle();
+
+    expect(env.visibleViews()).toEqual(["approve-network"]);
+    expect(env.pageErrors).toEqual([]);
+});

tests/backgroundApproval.test.js

@@ -397,7 +397,13 @@ function loadBackground(options) {
                 rpcResult = r;
             },
         );
-        return { result: () => rpcResult };
+        return {
+            id: () =>
+                new URL(created[created.length - 1].url).searchParams.get(
+                    "approval",
+                ),
+            result: () => rpcResult,
+        };
     }
 
     // A dApp asking to connect. The origin defaults to one the persisted
@@ -1484,6 +1490,55 @@ describe("what the approval is verified against", () => {
         });
     });
 
+    // Typed data whose domain names another chain is refused on the sign
+    // screen; a signature for it that reaches the background anyway is not
+    // handed to the page (https://git.eeqj.de/sneak/AutistMask/issues/519).
+    // TYPED_DATA names mainnet.
+    async function answerTypedData(bg, pending) {
+        const { domain, types, message } = JSON.parse(TYPED_DATA);
+        delete types.EIP712Domain;
+        const signature = await signer.signTypedData(domain, types, message);
+        const answer = bg.send(
+            {
+                type: "AUTISTMASK_SIGN_RESPONSE",
+                id: pending.id(),
+                approved: true,
+                signature,
+            },
+            { url: bg.fromPopup.url },
+        );
+        await settle();
+        return { answer, signature };
+    }
+
+    test("typed data for the active chain is handed back signed", async () => {
+        const bg = loadBackground();
+        const pending = bg.requestTypedData();
+        await settle();
+
+        const { answer, signature } = await answerTypedData(bg, pending);
+
+        expect(answer.sendResponse).toHaveBeenCalledWith({ signature });
+        expect(pending.result()).toEqual({ result: signature });
+    });
+
+    test("typed data for another chain is refused, not handed back", async () => {
+        const bg = loadBackground();
+        bg.setNetwork(SEPOLIA);
+        const pending = bg.requestTypedData();
+        await settle();
+
+        const { answer } = await answerTypedData(bg, pending);
+
+        const refusal =
+            "This typed data is for chain id 1, but the active network is Sepolia Testnet (chain id 11155111), so it cannot be signed.";
+        expect(answer.sendResponse).toHaveBeenCalledWith({
+            error: refusal,
+            retryable: false,
+        });
+        expect(pending.result()).toEqual({ error: { message: refusal } });
+    });
+
     test("a sign request from another address raises no approval at all", async () => {
         const bg = loadBackground();
         const pending = bg.requestSign(other.address);

tests/chainSwitchGate.test.js

@@ -16,7 +16,9 @@
 //
 // 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.
+// goes through storage rather than the shared state singleton. The last block
+// covers what the background tells open tabs when the user switches the
+// network in Settings.
 
 const { networkById } = require("../src/shared/networks");
 const { makeStorageStub } = require("./support/storageStub");
@@ -225,6 +227,14 @@ function loadBackground() {
         answerPrompt,
         closePrompt,
         opened,
+        // A message to the background from `sender`, and its answer.
+        send: (msg, sender) => {
+            let reply = null;
+            messageListener(msg, sender, (r) => {
+                reply = r;
+            });
+            return reply;
+        },
         walletState: () => storage.read("autistmask"),
         chainChangedEvents: () =>
             toTabs.filter((m) => m.eventName === "chainChanged"),
@@ -390,3 +400,109 @@ describe("only the user switches the network", () => {
         expect(bg.walletState().rpcUrl).toBe(CUSTOM_RPC);
     });
 });
+
+// Switching the network in Settings tells open pages, as an approved site
+// request does (https://git.eeqj.de/sneak/AutistMask/issues/500). These drive
+// the real Settings view over the background's storage, with what it sends
+// delivered to the background from the extension's own page.
+describe("switching the network in Settings tells every open tab", () => {
+    const POPUP = { url: EXT_URL + "src/popup/index.html" };
+
+    // A stand-in for one DOM node: enough of an element for init() to set
+    // properties on it and hang listeners off it.
+    function fakeElement() {
+        return {
+            value: "",
+            checked: false,
+            textContent: "",
+            style: {},
+            dataset: {},
+            classList: { add() {}, remove() {} },
+            listeners: {},
+            addEventListener(event, handler) {
+                this.listeners[event] = handler;
+            },
+            querySelectorAll: () => [],
+        };
+    }
+
+    // Settings, opened the way the popup opens it. Returns its network
+    // selector.
+    async function openSettings(bg) {
+        const elements = {};
+        const element = (id) => (elements[id] ||= fakeElement());
+        jest.doMock("../src/popup/views/helpers", () => ({
+            $: element,
+            showView: () => {},
+            updateDebugBanner: () => {},
+            showFlash: () => {},
+            escapeHtml: (s) => s,
+            flashCopyFeedback: () => {},
+            goBack: () => {},
+            pushCurrentView: () => {},
+            onViewLeave: () => {},
+            VIEWS: [],
+        }));
+        global.chrome.runtime.sendMessage = (msg) => {
+            bg.send(msg, POPUP);
+        };
+        await require("../src/shared/state").loadState();
+        require("../src/popup/views/settings").init({
+            pageClosed: new AbortController().signal,
+        });
+        const select = element("settings-network");
+        select.value = "mainnet";
+        return select;
+    }
+
+    // The user picks `networkId` in the selector.
+    async function choose(select, networkId) {
+        select.value = networkId;
+        await select.listeners.change();
+        await settle();
+    }
+
+    afterEach(() => {
+        jest.dontMock("../src/popup/views/helpers");
+    });
+
+    test("switching to the other network sends chainChanged once, with its chain id", async () => {
+        const bg = loadBackground();
+        const select = await openSettings(bg);
+
+        await choose(select, "sepolia");
+
+        expect(bg.walletState().networkId).toBe("sepolia");
+        expect(bg.chainChangedEvents()).toEqual([
+            {
+                type: "AUTISTMASK_EVENT",
+                eventName: "chainChanged",
+                data: SEPOLIA.chainId,
+            },
+        ]);
+    });
+
+    test("choosing the network already active changes nothing and sends nothing", async () => {
+        const bg = loadBackground();
+        const select = await openSettings(bg);
+        const before = bg.walletState();
+
+        await choose(select, "mainnet");
+
+        expect(bg.walletState()).toEqual(before);
+        expect(bg.chainChangedEvents()).toEqual([]);
+    });
+
+    test("a page cannot make the background send chainChanged", async () => {
+        const bg = loadBackground();
+
+        const reply = bg.send(
+            { type: "AUTISTMASK_NETWORK_CHANGED", chainId: SEPOLIA.chainId },
+            { url: CONNECTED_ORIGIN + "/" },
+        );
+        await settle();
+
+        expect(reply).toEqual({ error: "Unauthorized sender" });
+        expect(bg.chainChangedEvents()).toEqual([]);
+    });
+});

tests/e2e/firefox/driver.js

@@ -279,12 +279,18 @@ class Driver {
 
     // Shown means shown: in the popup a view is switched by toggling a
     // "hidden" class, and an element that is present but collapsed is not
-    // the thing a test means by visible.
+    // the thing a test means by visible. Until the page's stylesheet has
+    // applied that class hides nothing and every view lays out, so the page
+    // must also have finished loading, which it does only after its
+    // stylesheet, and neither the element nor anything enclosing it may
+    // carry the class (https://git.eeqj.de/sneak/AutistMask/issues/502).
     async waitVisible(selector, timeout = DEFAULT_WAIT_MS) {
         return this.waitFor(
             "selector " + selector + " to be visible",
             `const el = document.querySelector(arguments[0]);
-             if (!el) return false;
+             if (document.readyState !== "complete" || !el) return false;
+             if (el.closest(".hidden")) return false;
+             if (getComputedStyle(el).visibility !== "visible") return false;
              const r = el.getBoundingClientRect();
              return r.width > 0 && r.height > 0;`,
             [selector],

tests/e2e/firefox/run.js

@@ -128,6 +128,18 @@ step("the popup is drawn in the monospace font it declares", async (env) => {
     );
 });
 
+// The same check as the Chrome suite's (#456), so both browsers are held to
+// the same size.
+step("the popup's text is drawn at the 14px text-sm declares", async (env) => {
+    const size = await env.driver.execute(
+        "return getComputedStyle(document.body).fontSize;",
+    );
+    assert(
+        size === "14px",
+        "the popup's text is drawn at " + size + ", not at the 14px of text-sm",
+    );
+});
+
 // The recovery screen (#361): the Chrome suite's four cases, run before any
 // wallet exists for the same reason. With no wallet nothing saves on a timer,
 // so no save can write a good record over the unreadable one. The last of them

tests/e2e/harness.js

@@ -333,8 +333,33 @@ async function launch(routeOpts) {
 
 const PASSWORD = "e2e-harness-password";
 
+// Waits until the page shows `selector`, not only until it lays out. Until the
+// page's stylesheet has applied, the `hidden` class that showView() keeps on
+// every view but the current one hides nothing and every view lays out, so a
+// test could read a screen before the page's script had filled it
+// (https://git.eeqj.de/sneak/AutistMask/issues/502). So the page must also
+// have finished loading, which it does only after its stylesheet, and neither
+// the element nor anything enclosing it may carry `hidden`. Polled on a timer:
+// animation frames are not guaranteed to a window that is not in front.
 async function visible(page, selector, timeout = 15000) {
-    await page.waitForSelector(selector, { state: "visible", timeout });
+    await page
+        .waitForFunction(
+            (sel) => {
+                const el = document.querySelector(sel);
+                if (document.readyState !== "complete" || !el) return false;
+                if (el.closest(".hidden")) return false;
+                if (getComputedStyle(el).visibility !== "visible") return false;
+                const r = el.getBoundingClientRect();
+                return r.width > 0 && r.height > 0;
+            },
+            selector,
+            { polling: 50, timeout },
+        )
+        .catch((e) => {
+            throw new Error(
+                "the page did not show " + selector + ": " + e.message,
+            );
+        });
 }
 
 // An empty WebAssembly module: magic number and version header, no

tests/e2e/run.js

@@ -113,6 +113,18 @@ test("the popup is drawn in the monospace font it declares (#418)", async (env)
     );
 });
 
+// The same stylesheet sets the size on body to 75%, which would draw the
+// popup at 12px.
+test("the popup's text is drawn at the 14px text-sm declares (#456)", async (env) => {
+    const size = await env.page.evaluate(
+        () => getComputedStyle(document.body).fontSize,
+    );
+    assert(
+        size === "14px",
+        "the popup's text is drawn at " + size + ", not at the 14px of text-sm",
+    );
+});
+
 // The empirical half of #182. The manifest change is only a claim about
 // what the CSP permits; this is the observation. Two things have to hold
 // together, and the run covers both: the popup realm compiles WASM (here),
@@ -4538,6 +4550,42 @@ test("a site's network switch changes nothing until the user approves it (#408)"
     );
 });
 
+// Switching the network in Settings tells the page too, as an approved site
+// request does (https://git.eeqj.de/sneak/AutistMask/issues/500). The wallet
+// goes back to mainnet the same way at the end.
+test("a network switch in Settings tells the page (#500)", 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;
+    await openSettings(env.page);
+
+    await env.page.selectOption("#settings-network", "sepolia");
+    let 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 switch to Sepolia: " +
+            JSON.stringify(events),
+    );
+
+    await env.page.selectOption("#settings-network", "mainnet");
+    events = await chainChangedEvents(env.dapp, eventsBefore + 2);
+    assert(
+        events.length === eventsBefore + 2 &&
+            events[events.length - 1].data === mainnet.chainId,
+        "the page was not told of the switch back to mainnet: " +
+            JSON.stringify(events),
+    );
+    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/nativeCurrency.test.js

@@ -345,10 +345,10 @@ describe.each([
 });
 
 // A transaction's value and fee are in the native currency of the network the
-// transaction is on, which need not be the active one. A site can switch the
-// active network after its transaction is prepared and back before it is
-// signed, and a popup opened after a switch shows a sent or listed transaction
-// again. The wallet's balances follow the active network; these do not.
+// transaction is on, which need not be the active one. The active network can
+// change, in Settings or when the user approves a site's request, after a
+// transaction is prepared and change back before it is signed, and a popup
+// opened after a switch shows a sent or listed transaction again. The wallet's balances follow the active network; these do not.
 describe.each([
     ["mainnet", "sepolia", "ETH"],
     ["sepolia", "mainnet", "SepoliaETH"],

tests/phishingDomains.test.js

@@ -89,6 +89,12 @@ describe("vendored blocklist", () => {
         expect(isPhishingDomain(LISTED[0].toUpperCase())).toBe(true);
     });
 
+    test("a hostname ending in a dot is the same host", () => {
+        expect(isPhishingDomain(LISTED[1] + ".")).toBe(true);
+        expect(isPhishingDomain("wallet." + LISTED[1] + ".")).toBe(true);
+        expect(isPhishingDomain(CLEAN[0] + ".")).toBe(false);
+    });
+
     test("returns false for an empty or missing hostname", () => {
         expect(isPhishingDomain("")).toBe(false);
         expect(isPhishingDomain(null)).toBe(false);
@@ -133,6 +139,13 @@ describe("hostnameVariants", () => {
     test("lowercases hostnames", () => {
         expect(hostnameVariants("Evil.COM")).toEqual(["evil.com"]);
     });
+
+    test("drops the trailing dot of a fully qualified hostname", () => {
+        expect(hostnameVariants("sub.evil.com.")).toEqual([
+            "sub.evil.com",
+            "evil.com",
+        ]);
+    });
 });
 
 describe("domain hashing", () => {

tests/support/popupBoot.js

@@ -238,6 +238,10 @@ async function settle() {
  * @param {object} [options]
  * @param {object} [options.storage] a storage stub from makeStorageStub(), for
  *     a test that needs to make writes fail or to watch the round trips.
+ * @param {string} [options.search] the page URL's query string, such as
+ *     "?approval=" and an id for the popup opened as an approval window.
+ * @param {object} [options.runtime] members of chrome.runtime that replace the
+ *     stub's own, for a test that has to answer the background's messages.
  * @returns {Promise<object>} handles onto the booted page.
  */
 async function bootPopup(stored, options) {
@@ -281,12 +285,13 @@ async function bootPopup(stored, options) {
             sendMessage: jest.fn(async () => ({})),
             getURL: (p) => "chrome-extension://autistmask/" + p,
             onMessage: { addListener: () => {} },
+            ...(options && options.runtime),
         },
     };
     globalThis.document = document;
     globalThis.window = {
         location: {
-            search: "",
+            search: (options && options.search) || "",
             href: "chrome-extension://autistmask/src/popup/index.html",
             reload: () => reloads.push(Date.now()),
         },

tests/typedDataPermit.test.js

@@ -240,6 +240,7 @@ function request(data) {
 beforeEach(() => {
     state.trackedTokens = [];
     state.wallets = [];
+    state.networkId = "mainnet";
 });
 
 describe("a token permission is warned about, naming spender and amount", () => {
@@ -532,3 +533,66 @@ describe("the sign screen refuses a mismatched primary type", () => {
         expect(node("btn-approve-sign").disabled).toBe(true);
     });
 });
+
+// EIP-712: a wallet refuses typed data whose domain names a chain other than
+// the active one, because the signature is valid on the chain it names
+// (https://git.eeqj.de/sneak/AutistMask/issues/519). The wallet is on Sepolia
+// and the site asks for a mainnet USDC Permit.
+describe("the sign screen refuses typed data for another chain", () => {
+    const REFUSAL =
+        "This typed data is for chain id 1, but the active network is Sepolia Testnet (chain id 11155111), so it cannot be signed.";
+
+    function withChainId(chainId) {
+        return { ...PERMIT, domain: { ...PERMIT.domain, chainId } };
+    }
+
+    beforeEach(() => {
+        decryptWithPassword.mockClear();
+        state.networkId = "sepolia";
+    });
+
+    test("another chain shows the error, with Sign disabled", async () => {
+        await openSignScreen(PERMIT);
+        expect(node("approve-sign-error").textContent).toBe(REFUSAL);
+        expect(node("btn-approve-sign").disabled).toBe(true);
+    });
+
+    test("Sign clicked anyway decrypts and signs nothing", async () => {
+        const sent = await openSignScreen(PERMIT);
+        node("approve-sign-password").value = "any password";
+        await click("btn-approve-sign");
+
+        expect(decryptWithPassword).not.toHaveBeenCalled();
+        expect(sent.map((msg) => msg.type)).not.toContain(
+            "AUTISTMASK_SIGN_RESPONSE",
+        );
+        expect(node("approve-sign-error").textContent).toBe(REFUSAL);
+    });
+
+    // ethers signs 1, "1" and "0x1" as the same chain id.
+    test("the chain id is refused in each form ethers signs", () => {
+        for (const chainId of [1, "1", "0x1"]) {
+            expect(typedDataRefusal(request(withChainId(chainId)))).toBe(
+                REFUSAL,
+            );
+        }
+    });
+
+    test("a chain id that is not a number is refused", () => {
+        expect(typedDataRefusal(request(withChainId("mainnet")))).toBe(
+            "This typed data cannot be read, so it cannot be signed.",
+        );
+    });
+
+    test("the active chain leaves Sign enabled", async () => {
+        await openSignScreen(withChainId("0xaa36a7"));
+        expect(node("approve-sign-error").textContent).toBe("");
+        expect(node("btn-approve-sign").disabled).toBe(false);
+    });
+
+    test("no chain id leaves Sign enabled", async () => {
+        await openSignScreen(withChainId(undefined));
+        expect(node("approve-sign-error").textContent).toBe("");
+        expect(node("btn-approve-sign").disabled).toBe(false);
+    });
+});

tests/walletDefects.test.js

@@ -153,6 +153,18 @@ describe("the explanatory copy", () => {
         expect(all).not.toMatch(/\blost\b|\bstolen\b|\bgone\b/i);
     });
 
+    // The wallet holds the imported key but will not export it, so the copy
+    // must name every key the user may hold that reaches the addresses
+    // outside it.
+    test("it names the keys that reach the addresses outside this wallet", () => {
+        const body = defect.paragraphs.join(" ");
+
+        expect(body).toMatch(/private key export are disabled/);
+        expect(body).toMatch(
+            /with the extended private key you imported, if you kept a copy of it, or with the master extended private key or recovery phrase it came from, in software that repeats the same non-standard derivation/,
+        );
+    });
+
     test("it says the wallet is not deleted and what the user can do", () => {
         const body = defect.paragraphs.join(" ");