[Windows desktop] Clicking the slash-command menu scrollbar closes the menu

Description

In the Codex desktop app on Windows, clicking or dragging the scrollbar in the slash-command menu immediately dismisses the entire menu. The list can only be scrolled reliably with the mouse wheel or keyboard.

Steps to reproduce

1. Open a task in the Codex desktop app.
2. Focus the composer and type / to open the command menu.
3. Make sure the menu contains enough items to show the vertical scrollbar.
4. Click the scrollbar thumb or try to drag it.

Expected behavior

The command list scrolls while the menu remains open.

Actual behavior

The menu closes immediately when the scrollbar is clicked or dragged. Mouse-wheel scrolling works normally.

Environment

• Codex desktop app: 26.721.4979.0
• OS: Windows x64
• Install channel: Microsoft Store
• UI language: Simplified Chinese

Workaround

Use the mouse wheel, touchpad scrolling, or keyboard arrow/Page Up/Page Down keys.

Additional context

The issue becomes easier to notice when enough skills or commands are installed to make the command list overflow. It does not appear to be caused by any specific skill. The scrollbar may be getting treated as an outside-click target by the popup dismissal handler.