Codex Desktop: add-project submenu closes when cursor crosses auto-hidden sidebar boundary

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

26.616.51431 (bundle 4212)

What subscription do you have?

ChatGPT Pro (USD $100/month plan)

What platform is your computer?

Darwin 25.5.0 arm64 arm (macOS 26.5.1, build 25F80)

What issue are you seeing?

When the Codex App left sidebar is hidden/collapsed and temporarily revealed by hovering the sidebar toggle/left edge, the add-project submenu does not stay open across the sidebar boundary.

After clicking the add-project button in the Projects section, a submenu appears with "Start from scratch" and "Use an existing folder." The submenu extends partly outside the right edge of the sidebar. If the pointer stays on the part of the submenu that is still inside the sidebar boundary, it remains visible. If the pointer moves to the right side of the same submenu, outside the sidebar boundary, the sidebar auto-hides and the submenu closes, preventing selection of "Use an existing folder."

There is no error message. This appears to be a hover/focus-region issue: a child submenu opened from the auto-hidden sidebar is not treated as part of the active sidebar interaction region once it extends outside the sidebar bounds.

What steps can reproduce the bug?

1. Open Codex App on macOS.
2. Put the left sidebar in the hidden/collapsed auto-hide state.
3. Move the mouse to the top-left sidebar toggle/left edge so the sidebar temporarily appears.
4. In the Projects section, click the add-project button.
5. Observe the submenu with "Start from scratch" and "Use an existing folder." The submenu crosses the right edge of the sidebar.
6. Move the pointer over the left part of that submenu, still inside the sidebar boundary. The sidebar stays visible.
7. Move the pointer over the right part of the same submenu, outside the sidebar boundary, such as over the option text/body. The sidebar hides and the submenu closes.

Actual result:
The sidebar auto-hides when the pointer crosses the sidebar boundary, even though the pointer is still over the child add-project submenu. This makes the "Use an existing folder" option unreliable or impossible to select.

Session id, token limit usage, and context window usage do not seem applicable; this is a desktop UI interaction issue.

What is the expected behavior?

When a child menu or popover is opened from the auto-hidden sidebar, the sidebar should remain active while the pointer is over that child menu, even if the child menu extends outside the sidebar bounds.

The add-project submenu should remain visible and selectable until the user chooses an option, dismisses the menu, or moves outside both the sidebar and the submenu.

Additional information

Additional observation for the boundary behavior:

The failure appears to depend on the pointer crossing the right edge of the temporary sidebar, not on leaving the submenu itself.

• Hovering the sidebar toggle/left edge reveals the hidden sidebar.
• Clicking the add-project button in the Projects row opens the submenu.
• When the pointer remains over the part of that submenu that is still within the sidebar bounds, the sidebar stays open.
• When the pointer moves over the part of the same submenu that extends into the main content area, the sidebar auto-hides and the submenu closes.

This suggests the child add-project submenu is not included in the sidebar's active hover/focus region once it extends outside the sidebar bounds.

GitHub suggested possible duplicate issues while drafting (#23336 and #19838), but this seems distinct: it is not a project move/unpin hang and not a file-tree rename flicker. The repro is specifically the auto-hidden sidebar closing while the pointer moves into a child add-project submenu that crosses the sidebar boundary.

I searched for related Codex Desktop sidebar/add-project menu issues before filing and did not find an obvious exact duplicate.