fix(next): append Quote in Reply after composer draft
Quote in Reply appends a rendered Markdown block after the current draft and leaves the caret below it. Repeated quotes keep their order; selected text that resembles a reference definition stays visible and serialized. The existing muted left bar supplies the quote treatment, matching the Claude desktop quote reference while retaining cmux's colours and glass.
Leo: “I feel like putting it at the very lowest bit makes sense”.
Canonical route: chat.quoteReply({markdown}) from #26660 → ComposerHandle.quoteReply(markdown) here. The standalone composer head does not register that page action. #26654 is closed as superseded.
Before / after
| Before: existing draft | After: quote appended, typed reply outside it |
|---|---|
 |  |
 |  |
| Focused draft | Successive quotes keep their order |
|---|---|
 |  |
 |  |
Persistence review repair
Current repair head: 917f6261d65a9c08b214ef04dd9146955a53e671, tree 6aa173e4198d9937442a547beb81d1a4c9d1ef39. This is a normal fast-forward from reviewed head 04c96e958babccef9aac7b215a6f818709fe74ec; no base merge or rebase.
Addresses the quote-only draft persistence finding. The serializer now preserves a blank-line boundary when an empty reply paragraph follows a block. Existing restore logic recreates that paragraph, so reopening keeps the end caret outside the quote. Ordinary paragraph drafts retain their existing trimming behavior. Canonical Quote in Reply insertion and native/menu routes are unchanged.
The new browser fixture mounts the real Composer, calls ComposerHandle.quoteReply and settleDraft, unmounts/remounts the Composer/editor, types through Playwright, and checks the actual onSend Markdown. Only daemon draft storage is a fixture. Both quote-only and existing typed drafts are covered.
Fleet red/green proof 40876007269 runs the exact browser regression against the old serializer and confirms both swallowed-reply failures; with the repaired serializer, the complete web check and all 33 focused tests / 107 assertions pass. The run's overall conclusion is FAILURE because its shell cleanup used a relative path after changing directories; the source tree and all test results are retained. Final hosted run 40876648578 is SUCCESS at the pushed repair head and identical tree: the static gate fetches the real immutable base/head history and reports no new violations; both browser save/unmount/reopen/type/send cases pass (8 assertions).
Earlier review and integrated-capture receipts below apply to their stated heads. Fresh review belongs to the existing landing workflow.
Performance
No perf numbers: this is a persistence correctness repair with behavioral browser and editor tests; it makes no measured performance claim.
Prior verification
Dependency: #26660 must land first. This standalone head’s gallery health reports agent-pane.quote-reply#append waiting for the unregistered page action (run 40655066591); the combined proof below passes that interaction. The PR’s own four react-apps-check shards pass. This gallery failure is an own dependency failure, not a base-red exemption.
Frozen head: 8d19f6d54f558aa6bbf7e68ecdec47f649d15f25.
Review (codex gpt-6-astra xhigh): SHIP at 8d19f6d54f558aa6bbf7e68ecdec47f649d15f25.
Focused quote/editor/selection/message regression suites pass (42 tests on the combined production). The earlier three attachment-paste failures also reproduce on base; no attachment code changed. All heavy verification ran on the fleet.
Integrated proof combines #26660 producer 655393f0d31ee7cbac3d5fbc2847a40cfcd3c48b and #26655 composer 8d19f6d54f558aa6bbf7e68ecdec47f649d15f25. Production merge: 04ce1974a450849f27cb5258e430592bfb9802fc; capture candidate: b95c200fae699529cb2bfda166daa1f07d38af93, tree 1feeaebb269fb3736185409bad271553dc54edee. Later candidate commits change only the capture test, not either survivor branch.
Fleet run 40664890704 is SUCCESS: eight light/dark gallery interactions/captures, full web check, localization scanners and web lint. Six post-type observations assert the action is registered, the draft stays first, one or two rendered quotes stay ordered, the caret/typed reply is in the trailing paragraph, and Markdown round-trips with blank lines. Root inspected all eight images. Zero-step gallery status none is accepted only for an empty measurement list without errors, followed by the actual DOM/serialization assertions; it is not a performance pass.
Review (codex gpt-6-astra xhigh): SHIP at b95c200fae699529cb2bfda166daa1f07d38af93 (isolated integration; static review). Native compile/runtime is separate and remains unverified; Swift HOLD #26809 still applies to #26660. Captures use a public-safe fixture, never Leo's private references.
Changelog
Fixed: Quote in Reply stays below the draft, renders as a quote, preserves selected text, and leaves a ready-to-type paragraph.
Agent session: agent session