static/app.js carried a near-verbatim copy of the prompt-recall logic in
static/js/composerArrowUpRecall.js, wired as a second capture-phase
keydown listener on the same #message textarea. The copy omitted the
draft guard the module has: it called preventDefault() and
stopImmediatePropagation() unconditionally, then recalled history[0]
over whatever the user had typed.
Because it stopped immediate propagation, the copy won regardless of
registration order — if it ran first the module never saw the event, and
if it ran second the module had already declined to stop propagation on
an unmatched draft. The guard at composerArrowUpRecall.js:109 was
unreachable on the real page, so ArrowUp on a multi-line draft replaced
it with the last sent prompt instead of moving the caret up a line.
Delete the duplicate. The module keeps ownership of ArrowUp/ArrowDown
recall, which is the behavior MODULE_SUMMARY.md documents ("on an empty
composer") and the behavior tests/test_composer_arrow_up_recall_js.py
already pins via test_non_empty_composer_does_not_recall and
test_multiline_caret_navigation_preserved.
Also correct a stale comment in the module that described the deleted
behavior and contradicted the guard 35 lines above it, and add a
regression test asserting app.js does not reintroduce a second handler.
Fixes#5862
Pressing ArrowUp on an empty #message composer restores the last sent user text, matching common chat-app UX (Slack, Discord, ChatGPT).
- Read from #chat-history .msg-user dataset.raw (same path as resend/regenerate), not session sidebar metadata
- Literal empty check (whitespace-only drafts are preserved); ignore Shift/Alt/Ctrl/Meta and IME composition
- Extract wiring to composerArrowUpRecall.js; rAF + 250ms retry only (no global MutationObserver)
- Add tests/test_composer_arrow_up_recall_js.py
Co-authored-by: Cursor <cursoragent@cursor.com>
