NOTE: Editor appears to freeze but it's not really frozen but instead stops responding to mouse input.

Steps to reproduce:

1. Create a new URP Project
2. Navigate to Edit > Preferences > Search and switch "Object Selector" to "Advanced"
3. Navigate to Edit > Project Settings > Graphics
4. Switch the Asset for "Default Render Pipeline" to any
5. Once the native DialogBox opens, switch to another app and then back to Unity

Actual results: The Editor stops responding to mouse input but keyboard can be used to dismiss the dialog.

Expected results: DialogBox can be dismissed with mouse click

Reproducible with versions: 6000.3.0a1, 6000.3.5f1, 6000.4.0b5, 6000.5.0a4

Not reproducible with versions: 6000.0.66f1, 6000.1.16f1, 6000.2.0b2, 6000.2.15f1

Tested on (OS): Windows 11

Notes:

• Only seems to be an issue with this specific scenario, i.e. native DialogBox opened by Advanced Search window (doesn't occur with other dialogs)
• Dismissing the dialog without switching apps can still sometimes hit this issue but it appears infrequent

Workaround:

Click the MainWindow's title bar to focus the dialog box, and then use the keyboard to dismiss it. That is, select a button with the arrow keys and press Enter.

{}Update:{}{}{}

The original fix didn't completely solve the issue, and the bug still repros, though it's now less frequent. A "complete" fix is in progress.