Steps to reproduce:
1. Open the attached project
2. Open CharSheet.uxml in UI Builder
3. Select the Label element
4. Right mouse button click on the purple icon next to its Text property
5. Click Edit binding
6. Click inside the Data Source Path field
7. Try to click away from it inside the Edit Binding window

Expected result: the dropdown will disappear
Actual result: the dropdown stays (the video is not showing pointer actions, but there are is clicking in it)

Reproducible with: 2023.2.0a18, 2023.3.0a3

Note: Linux, Windows tested.
Tested using Ubuntu 22.04 and Windows 10.