Best possible solution:

Land this small replacement only after branch-specific mobile Safari proof shows no global scrollbar and no composer-focus zoom, while keeping the source PR credited and linked.

Do we have a high-confidence way to reproduce the issue?

Yes from source evidence: the related source PR describes opening the Control UI chat on iPhone Safari, observing the global scrollbar/full-height issue, and focusing the composer input. I did not run a live iPhone Safari reproduction in this read-only review.

Is this the best way to solve the issue?

Yes, with proof still needed: removing the chat-only duplicate height is a narrow fix because base .shell already owns viewport sizing and the 16px input/max-scale concern is handled elsewhere. Branch-specific Safari proof is the remaining merge gate.

AGENTS.md: found and applied where relevant.

Codex review notes: model internal, reasoning high; reviewed against 7f49f875de1b.

Label changes:

• add P2: This is a normal-priority visible mobile web UI bug fix with limited blast radius.
• add proof: 📸 screenshot: Contributor real behavior proof includes screenshot evidence. The linked source PR has screenshots, but this replacement PR still needs after-fix proof for the exact branch; update the PR body with redacted evidence to trigger a fresh review, or ask a maintainer for @clawsweeper re-review.
• add rating: 🦪 silver shellfish: Overall readiness is 🦪 silver shellfish; proof is 🦪 silver shellfish and patch quality is 🐚 platinum hermit.
• add status: 📣 needs proof: The PR needs real behavior proof before ClawSweeper can clear the contributor ask. Needs stronger real behavior proof before merge: The linked source PR has screenshots, but this replacement PR still needs after-fix proof for the exact branch; update the PR body with redacted evidence to trigger a fresh review, or ask a maintainer for @clawsweeper re-review.

Label justifications:

• P2: This is a normal-priority visible mobile web UI bug fix with limited blast radius.
• rating: 🦪 silver shellfish: Overall readiness is 🦪 silver shellfish; proof is 🦪 silver shellfish and patch quality is 🐚 platinum hermit.
• status: 📣 needs proof: The PR needs real behavior proof before ClawSweeper can clear the contributor ask. Needs stronger real behavior proof before merge: The linked source PR has screenshots, but this replacement PR still needs after-fix proof for the exact branch; update the PR body with redacted evidence to trigger a fresh review, or ask a maintainer for @clawsweeper re-review.
• proof: 📸 screenshot: Contributor real behavior proof includes screenshot evidence. The linked source PR has screenshots, but this replacement PR still needs after-fix proof for the exact branch; update the PR body with redacted evidence to trigger a fresh review, or ask a maintainer for @clawsweeper re-review.

PR surface:

Source -8. Total -8 across 1 file.

Acceptance criteria:

• [P1] Provide or inspect real iPhone Safari proof for chat viewport height and composer focus/zoom behavior.
• [P1] Verify pnpm check:changed and pnpm ui:build results if maintainers want command proof before merge.

What I checked:

• Repository policy read: Root and UI-scoped review guidance were read fully; the UI proof requirement and scoped Control UI guidance apply to this review. (AGENTS.md:1, 7f49f875de1b)
• PR diff: The replacement branch only deletes .shell--chat min-height: 100vh, height: 100vh, and the chat-specific 100dvh override, leaving overflow: hidden. (ui/src/styles/layout.css:34, 62f0150349f9)
• Current shell sizing: Current main already gives .shell height: 100vh plus a 100dvh override, so the chat-specific duplicate height is not the primary owner of shell viewport sizing. (ui/src/styles/layout.css:13, 7f49f875de1b)
• Chat entry point: The chat route renders class="shell ... shell--chat" and main.content.content--chat, so this CSS affects the active Control UI chat layout path. (ui/src/ui/app-render.ts:2244, 7f49f875de1b)
• Maximum-scale review context: The source PR review comments objected to maximum-scale=1 and recommended preserving pinch zoom by using 16px form-control sizing instead. (ui/index.html:5, e23133c4ed60)
• Current targeted input sizing: Current main keeps the viewport meta free of maximum-scale, defines the Control UI input text size as at least 16px, and the chat composer textarea uses that variable. (ui/src/styles/chat/layout.css:623, 7f49f875de1b)

Likely related people:

• BunsDev: Recent live GitHub commit history shows repeated Control UI layout, chat, accessibility, and text-size work touching the same CSS surfaces. (role: likely UI layout owner; confidence: high; commits: 52370c59980b, 28f59a9124a4, f76a3c5225bb; files: ui/src/styles/layout.css, ui/src/styles/base.css, ui/src/styles/chat/layout.css)
• steipete: Recent live GitHub history includes calm composer and chat control work on the related composer/layout path. (role: recent chat composer contributor; confidence: medium; commits: 2b30951b8090, d328a0d7a0da; files: ui/src/styles/chat/layout.css, ui/src/styles/layout.css)
• NianJiuZst: Recent live GitHub history includes same-file layout fixes around chat/sidebar stacking and content--chat. (role: recent adjacent layout contributor; confidence: medium; commits: b01a54de6f0c; files: ui/src/styles/layout.css)

• 🦀 challenger crab: rare, exceptional readiness with strong proof, clean implementation, and convincing validation.
• 🦞 diamond lobster: very strong readiness with only minor maintainer review expected.
• 🐚 platinum hermit: good normal PR, likely mergeable with ordinary maintainer review.
• 🦐 gold shrimp: useful signal, but proof or patch confidence is still limited.
• 🦪 silver shellfish: thin signal; proof, validation, or implementation needs work.
• 🧂 unranked krab: not merge-ready because proof is missing/unusable or there are serious correctness or safety concerns.
• 🌊 off-meta tidepool: rating does not apply to this item.

Shiny media proof means a screenshot, video, or linked artifact directly shows the changed behavior. Runtime, network, CSP, and security claims still need visible diagnostics.

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