Agent chat: a prompt's floating Copy no longer covers its bubble
Problem
The layout pass (2026-10-20) found that the Copy button overlaps a prompt bubble's text. The transcript's floating Copy, shown on keyboard focus or for a selected range, sits at the row's top-right corner. A prompt's bubble is drawn there too, right-aligned and up to 70% wide, so the button covered the text.
Change
A prompt row's floating Copy moves to the row's top-left corner, which the bubble never reaches (conversation.css, .acpmux-row.acpmux-user .acpmux-row__copy). Other rows keep it at the right. The button and its keyboard and range-copy behaviour are unchanged.
The other defect in the same report (steer marks drawn as sentences under bubbles) is fixed by #22773, which removes SteerMark.
Observed / Not run
- Ran
scripts/web-lint.sh(passes) andscripts/cmux-next/prepush-gate.py(no new violations). - I didn't capture a before/after screenshot; the change is one CSS rule.
Changelog
- Fixed: In chat, the Copy button that appears on keyboard focus no longer covers your message's text.
Agent session: cosmic-gray
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Summary by cubic
Moves the floating Copy button in agent chat so it no longer covers a prompt's text. Shown on keyboard focus or for a selected range, the button sat at a row's top-right corner, where a prompt's right-aligned bubble (up to 70% wide) also draws. Prompt bubbles now show the button at the top-left corner, which the bubble never reaches; rows drawn as a line from the left edge keep it at the right, and the button's keyboard and range-copy behavior is unchanged.