#28798 cmux NEXT composer: one + menu for chat and New Tab, ChatGPT's shape, skills under /

Leo: "our + button is ass" / "inside chat and in the composer it's ass"

Draft: the first commit adds the gallery states and the shape test (red first). The fix, the stills and the table follow.

Changelog

none

Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Rebuilds chat and New Tab's + button as one shared menu in ChatGPT's shape: skills no longer get rows, they collapse to a single Skills… row that opens the slash list. Attach comes first, then the composer's actions and the searches, with group headers gone.

• Rows draw icon, title, and muted description on one line in a 340px-wide, 360px-tall panel that scrolls inside.
• New Tab's + draws the shared registry and covers the project and machine pills: Picker's overBackdrop renders the menu outside the composer's glass so its own glass frosts what's behind it, and the layer counts as composer chrome so a press on a row keeps the prompt's focus and the row takes the click.
• A Chromium test holds the new shape and writes light/dark stills to FAST_CHECKS_OUT; the Skills… strings ship in every language.