Clicking on tab stops click event propagation

[MetRonnie]

Description

Clicking on a tab in a tab bar does not cause in-DOM context menus to close etc.

Reproduce

1. Open something that depends on a click outside event to close, e.g. a Jupyter Lab context menu
2. Click on a tab title
3. The context menu remains open

Expected behavior

The context menu closes

Context

• Operating System and version: Windows 11
• Browser and version: Chrome 138, Edge 138
• JupyterLab version:
  @lumino/default-theme: 2.1.10
  @lumino/widgets: 2.7.1

Troubleshoot Output

Paste the output from running `jupyter troubleshoot` from the command line here.
You may want to sanitize the paths in the output.
N/A

Command Line Output

Paste the output from your command line running `jupyter lab` here, use `--debug` if possible.
N/A

Browser Output

Paste the output from your browser Javascript console here, if applicable.
N/A

[sccolbert]

Confirmed. The popup menus are rendered at the root document node with the highest precedence and trap all mouse events before they go elsewhere. This "should" be a simple detection of the mousedown event in the menu handler to see if it is outside the menu bounds. The timers on the submenus muddy the waters a bit. I'll look into it.