Font Asset Creator and Sprite Importer windows throw Window serialization errors when enabling or disabling UI Toolkit Live Reload option

Steps to reproduce:

1. Open the attached project
2. Right-click on the Font Asset Creator window's handle
3. Select the option to enable/disable the UI Toolkit Live Reload option
4. Observe the Console window

Actual results: "Window serialization will fail" error message is thrown every time the option is enabled/disabled

Expected results: No warnings or Errors are thrown when enabling or disabling the UI Toolkit Live Reload option for Text-related windows

Reproducible with versions: 6000.0.82f1, 6000.3.22f1, 6000.5.9f1, 6000.6.0b9, 6000.7.0a5

Tested on (OS): macOS 26.6.2