[ThomasK33]

Summary

The right sidebar's tab strip has a "+" (New tab) button again, right after the last tab, like the ChatGPT macOS app. Before, New tab was only a row at the bottom of the All tabs (chevron) menu. The chevron menu stays, so tabs that scroll out of view are still one pick away. It now lists every open tab, the New tab too.

Desktop	Narrow strip (390px viewport)

Background

#6995 moved New tab into the All tabs menu and removed the strip's "+" on every screen. A New tab hidden in a menu is hard to find, so the "+" is back.

Implementation

• NewTabButton sits outside the scrolling row, as a sibling of the tablist, so the tablist still owns only tabs. While the tabs fit, it follows the last tab. Once they overflow, the row scrolls and the "+" stays in view.
• It uses the strip's icon-button style, so it gets the 24px coarse-pointer target and the desktop no-drag region. Its tooltip shows the New tab shortcut (hidden on phones), and it sets aria-keyshortcuts.
• The All tabs menu has no New tab row now, so no separator is needed.
• Test helpers (jest UI, Storybook plays, Playwright, bug-bash repros) now open the New tab with the "+".

Validation

• Storybook interaction tests for the tab strip, RightSidebar, the seeded a11y pages, phone full-screen and phone viewports pass. The tablet touch-target check in .storybook/test-runner.ts now also covers the "+".
• Jest UI suites: layout/rightSidebar, review/focus, review/baseSelector and chat/contextUsageBoot pass.
• Bug bash in the sandbox: I ran 5 charters on this branch (mouse, keyboard, overflow plus reload, phone, split panes) with Sonnet 5.5 and the real app AI. They found 0 issues. One run cost $3.48 at list price. The run also gave 2 warnings, and both are older than this PR:
  • The tablist does not handle ArrowLeft and ArrowRight. I filed this as an issue (linked in a comment below).
  • Escape does not close a New tab. I rejected this one, because Escape closes no other tab.

Risks

Low, limited to the right sidebar's tab strip. The "+" takes about 26px from the tab row. On a pane at its minimum width, a long tab (240px) can show cut off at its end. I kept the 10rem cap of titlebar-safe-right-capped: a larger cap would put strip controls under the Windows/Linux window controls at the 300px minimum width. So these stories now check what still holds:

• Narrow is 330px wide (was 300px), so its 240px tab still fits beside "+" and All tabs.
• TabsReachableUnderWideTitlebarInset checks that the selected tab can be clicked, not that it is fully visible.

---

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-21T09:17:29.744959Z	e44439e	Manual request
🔒 Security Review	✅ Completed 2026-10-21T09:17:27.924377Z	e44439e	Manual request

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[ThomasK33]

Bug bash follow-up: the keyboard explorer's arrow-key warning is older than this PR. I filed it as #7102.

[ThomasK33]

@codex review

[chatgpt-codex-connector]

🛡️ Codex Security Review · Automatically triggered

Security review completed. No security issues were found in this pull request.

Reviewed commit: e44439ec74

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[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Breezy!

Reviewed commit: e44439ec74

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
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• Comment "@codex review".

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[ThomasK33]

Readiness record for head e44439ec74:

• CI: Required and Visual Regression Testing pass. Pixel / Review waits for a human sign-off at pixel.coder.com. It is not ruleset-required.
• Review rounds: 1. Codex found no issues, and the Codex security review found none. No review threads.
• Bug bash: 5 charters, 0 issues, $3.48. Pre-existing warning filed as 🤖 Right sidebar tab strip: ArrowLeft/ArrowRight do not move between tabs #7102.
• Independent advisor (clean context): ready with tracked follow-ups. Follow-up: 🤖 Right sidebar tab strip: selected tab cut off on narrow panes with a window-controls inset #7103 (selected tab cut off on narrow panes with a window-controls inset; trade-off stated under Risks).
• Decision: ready. Enqueuing in the merge queue.