How to reproduce:
1. Open the "GLES FLICKER" project
2. In Scene view, observe the viewport
3. In Game view, observe the viewport

Expected result: no flickering triangle in the viewport of the Scene view
Actual result: a flickering triangle covers half of the viewport in the Scene view

Reproduced with: 2022.2.4f1, 2022.2.10f1, 2023.1.0b7, 2023.2.0a6
Not reproduced with: 2020.3.46f1, 2022.2.3f1, 2023.1.0a20

Reproduced on: Windows 10 (by reporter), Windows 11

Notes:
1. Not reproducible if the main Graphics API for Windows is not set to OpenGLES3 or OpenGLCore - "OpenGLES3" or "OpenGLCore" must appear at the top of the list (Edit > Project Settings > Player > Other Settings > Graphics API for Windows)
2. Some versions will not reproduce if URP Scriptable Render Pipeline Setting is not set - use a URP sample asset (Edit > Project Settings > Graphics)
3. Some versions will not reproduce if URP Global Settings field is not set - use a URP sample asset (Edit > Project Settings > Graphics > URP Global Settings)