How to reproduce:
1. Open the user's attached project
2. In the Assets folder of the Project window, right-click > Create > UI Toolkit > UI Document
3. Observe the amount of time it takes to create the UI Document
Expected result: UI Document is created in 1-2 seconds
Actual result: UI Document may take up to 10 seconds to create
Reproducible with: 2021.2.0a18, 2021.3.4f1, 2022.1.4f1, 2022.2.0a15
Not reproducible with: 2020.3.35f1, 2021.2.0a17
Couldn't test with: 2019.4.39f1 (missing buttons for reproduction)
Note: During testing on Windows 10, creating a UI Document took ~2 seconds before the regression and ~5 seconds after