diff --git a/content.js b/content.js
index 898fdfa..e427061 100644
--- a/content.js
+++ b/content.js
@@ -240,12 +240,28 @@ function countDoneMsgs() {
 
 // The chat panel echoes the submitted prompt — the strongest "it stuck" signal, and
 // on a retry it means the PREVIOUS submit registered (so don't type it again).
+//
+// It must identify THIS prompt, not "a prompt that starts the same way". 2026-07-08: this
+// matched prompt.slice(0,60), and 13 of the 15 djsim_phonewall prompts opened with an
+// identical 60 chars ("The illustrated top picture-panel of a cheap 1979 promotiona"). The
+// previous task's echo was still on screen, so the driver decided every one of them had
+// already been submitted, never typed them, and sat out a 3-minute timeout. Thirteen times.
+//
+// No fixed slice is safe: djsim_phonewall needs 160 chars of PREFIX to disambiguate,
+// djsim_batch3 needs 190 chars of SUFFIX. So match the whole thing — or, if the DOM has
+// mangled the middle, require both ends in the same element.
+const normText = (s) => String(s).replace(/\s+/g, ' ').trim();
+
 function promptEchoed(prompt) {
-  const needle = String(prompt).slice(0, 60).trim();
-  if (!needle) return false;
-  return [...document.querySelectorAll('div, p, span')].some(e => visible(e) &&
-    !e.closest('[contenteditable="true"], textarea') &&
-    (e.textContent || '').includes(needle) && (e.textContent || '').length < needle.length + 500);
+  const full = normText(prompt);
+  if (full.length < 12) return false;
+  const head = full.slice(0, 100), tail = full.slice(-100);
+  return [...document.querySelectorAll('div, p, span')].some(e => {
+    if (!visible(e) || e.closest('[contenteditable="true"], textarea')) return false;
+    const t = normText(e.textContent || '');
+    if (t.length > full.length + 500) return false;   // that's a container, not the message
+    return t.includes(full) || (t.includes(head) && t.includes(tail));
+  });
 }
 
 // Flow's "Try again" button, shown beside the "Something went wrong" banner.
diff --git a/test_prompt_echo.mjs b/test_prompt_echo.mjs
new file mode 100644
index 0000000..c6fe360
--- /dev/null
+++ b/test_prompt_echo.mjs
@@ -0,0 +1,91 @@
+#!/usr/bin/env node
+// Regression test for promptEchoed(). Run: node test_prompt_echo.mjs
+//
+// 2026-07-08: promptEchoed matched prompt.slice(0,60). 13 of the 15 djsim_phonewall prompts
+// open with an identical 60 chars, so once Alien's prompt was echoed in the chat pane, every
+// later calendar looked "already submitted". The driver never typed them and sat out a 3-minute
+// timeout, thirteen times. This test pins the fix and documents the bug it replaced.
+
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+const HERE = path.dirname(fileURLToPath(import.meta.url));
+const BANK = path.join(HERE, 'banks', 'djsim_phonewall.jsonl');
+const prompts = Object.fromEntries(fs.readFileSync(BANK, 'utf8').trim().split('\n')
+  .map(l => { const r = JSON.parse(l); return [r.id, r.prompt]; }));
+
+const makeDoc = (msgs) => ({ querySelectorAll: () => msgs.map(m => ({ textContent: m, _editor: false })) });
+const visible = () => true;
+
+// The shipped implementation, kept in sync with content.js by hand (no bundler here).
+const normText = (s) => String(s).replace(/\s+/g, ' ').trim();
+function promptEchoed(prompt, document) {
+  const full = normText(prompt);
+  if (full.length < 12) return false;
+  const head = full.slice(0, 100), tail = full.slice(-100);
+  return [...document.querySelectorAll('div, p, span')].some(e => {
+    if (!visible(e) || e._editor) return false;
+    const t = normText(e.textContent || '');
+    if (t.length > full.length + 500) return false;   // that's a container, not the message
+    return t.includes(full) || (t.includes(head) && t.includes(tail));
+  });
+}
+
+// What it replaced — kept only to assert the bug is real, and stays fixed.
+function promptEchoedBuggy(prompt, document) {
+  const needle = String(prompt).slice(0, 60).trim();
+  if (!needle) return false;
+  return [...document.querySelectorAll('div, p, span')].some(e => visible(e) && !e._editor &&
+    (e.textContent || '').includes(needle) && (e.textContent || '').length < needle.length + 500);
+}
+
+let fails = 0;
+const check = (name, got, want) => {
+  if (got !== want) { fails++; console.log(`  FAIL  ${name} (got ${got}, want ${want})`); }
+  else console.log(`  ok    ${name}`);
+};
+
+// The exact scene: skylab and alien have been sent; their prompts sit in the chat pane.
+const chat = makeDoc([prompts.cal79_skylab, prompts.cal79_alien,
+  "I've created that 1979 Alien calendar illustration for you."]);
+
+console.log('the bug is real (old impl mistakes a shared 60-char opening for a match):');
+check('old impl false-positives joydivision', promptEchoedBuggy(prompts.cal79_joydivision, chat), true);
+check('old impl false-positives afghanistan', promptEchoedBuggy(prompts.cal79_afghanistan, chat), true);
+
+console.log('\nthe fix:');
+check('alien reads as echoed', promptEchoed(prompts.cal79_alien, chat), true);
+check('skylab reads as echoed', promptEchoed(prompts.cal79_skylab, chat), true);
+const unsent = Object.keys(prompts).filter(k => !['cal79_skylab', 'cal79_alien'].includes(k));
+const falsePos = unsent.filter(k => promptEchoed(prompts[k], chat));
+check(`all ${unsent.length} unsent prompts read as NOT echoed`, falsePos.length, 0);
+if (falsePos.length) console.log('    false positives:', falsePos);
+
+console.log('\nit still works as the "it stuck" signal:');
+const chat2 = makeDoc([prompts.cal79_alien, prompts.cal79_disco]);
+check('disco echoed once present', promptEchoed(prompts.cal79_disco, chat2), true);
+check('tmi still not echoed', promptEchoed(prompts.cal79_tmi, chat2), false);
+
+console.log('\nrobustness:');
+check('survives DOM whitespace reflow',
+  promptEchoed(prompts.cal79_disco, makeDoc([prompts.cal79_disco.replace(/ /g, '\n  ')])), true);
+check('a page-sized container does not count',
+  promptEchoed(prompts.cal79_tmi, makeDoc([Object.values(prompts).join(' ') + ' '.repeat(2000)])), false);
+check('empty prompt is never echoed', promptEchoed('', chat), false);
+
+// every bank must be self-distinguishable under the new rule
+console.log('\nevery bank:');
+for (const f of fs.readdirSync(path.join(HERE, 'banks')).filter(f => f.endsWith('.jsonl'))) {
+  const ps = fs.readFileSync(path.join(HERE, 'banks', f), 'utf8').trim().split('\n')
+    .map(l => JSON.parse(l).prompt);
+  const doc = makeDoc(ps);                       // pretend the whole bank was sent
+  const missed = ps.filter(p => !promptEchoed(p, doc)).length;
+  // and each prompt must NOT match a chat containing only the OTHER prompts
+  let cross = 0;
+  ps.forEach((p, i) => { if (promptEchoed(p, makeDoc(ps.filter((_, j) => j !== i)))) cross++; });
+  check(`${f}: ${ps.length} prompts, ${missed} missed, ${cross} cross-matched`, missed + cross, 0);
+}
+
+console.log(fails ? `\n${fails} FAILURE(S)` : '\nALL GREEN');
+process.exit(fails ? 1 : 0);