[Bug]: Lineage three-dot button hover background is misaligned with its icon

[arhammahajan]

Before submitting

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area

apps/web

Steps to reproduce

1. Open a thread with an active agent session.
2. Open the thread details panel and locate Lineage.
3. Hover over the three-dot “More thread actions” button.

Expected behavior

The three-dot icon should be centered within the button, with an evenly aligned hover background around it.

Actual behavior

The hover background is offset relative to the three-dot icon, making the button look incorrectly aligned.

The attached screenshot shows the affected button beside “Lineage”.

Impact

Cosmetic issue

Version or commit

T3 Code 0.0.46-nightly.20261003.2632

Environment

Ubuntu 26.04

Logs or stack traces

No relevant logs.

Screenshots, recordings, or supporting files

Screenshot From 2026-10-04 01-41-36.png

Workaround

None known.

[juliusmarminge]

Note

Grok responding on behalf of Julius.

Triage

Thanks for the report and the screenshot, @arhammahajan! I can confirm this on current main. The Lineage hover chip is a 24px square, and the three dots sit at its left edge, so the fill runs past the icon on the right. That matches your screenshot, which shows about 3px of fill before the dots and about 12px after. It's cosmetic, and I didn't find a duplicate.

The button is the "More thread actions" trigger in apps/web/src/components/chat/ThreadRelationshipsControl.tsx. It only appears when the thread has a provider session that can be detached (canDetachThreadProviderSession, meaning the session isn't stopped or error), which is why you see it during an active agent session.

It's a ThreadDetailsControl with part="icon". In the panel path, size and variant are ignored, so size="icon-xs" never reaches Button, whose base class includes justify-center. Instead, part="icon" uses THREAD_DETAILS_PANEL_ICON_ACTION_CLASS from apps/web/src/components/chat/threadDetailsPanelStyles.ts, which is size-6 (24px) with p-0. The shared panel control classes are inline-flex items-center without justify-center, so the size-3.5 icon stays at the start of the box, and the hover background fills the whole box.

The Automations icon buttons (manage, edit, run) use the same part="icon" class, so their hovers are probably offset the same way.

Likely fix area

• One option is to center the content in THREAD_DETAILS_PANEL_ICON_ACTION_CLASS, which would also fix the Automations buttons.
• Another is to let the panel path pass the Button size through, so its default centering applies.

A maintainer will decide on the fix direction.

[juliusmarminge]

Note

Grok responding on behalf of Julius.

Fixed by #15669 (fix(web): center icons in thread details icon buttons), now merged to main. The shared thread details icon button style now centers its contents, so the Lineage three-dot hover highlight lines up with the icon. Thanks for the report, @arhammahajan!