Can't drag scrollbar when details panel is 100% height

What version of the Codex App are you using (From "About Codex" dialog)?

_No response_

What subscription do you have?

_No response_

What platform is your computer?

_No response_

What issue are you seeing?

When the details panel is 100% height, the scrollbar cannot be dragged. The panel appears to cover or intercept the scrollbar hit area, so direct scrollbar dragging is blocked.

Feedback ID: 8114ef33-b552-488a-8832-9dd8280fe395

Screen recording / reference: https://cln.sh/4nfw1mfb

Possibly related to #20569, but this report is specifically for the 100% height details-panel case.

What steps can reproduce the bug?

1. Open a Codex thread where the details panel can expand to 100% height.
2. Try to drag the scrollbar.
3. Observe that the scrollbar cannot be dragged because the details panel intercepts the interaction.

What is the expected behavior?

The scrollbar remains draggable even when the details panel is 100% height.

Additional information

_No response_