How to reproduce:
1. Open the project “IN-92589_ClearFlagsPixelPerfect”
2. Enter Play Mode
3. Drag the Mouse Cursor outside of the blue box
4. Observe the Game Window

Expected result: The black borders are unaffected by the Mouse movements
Actual result: The Mouse Cursor leaves a trail of itself outside the Main Camera box

Reproducible with: 2023.3.0a18, 6000.0.33f1, 6000.1.0b1
Not reproducible with: 2022.3.55f1, 2023.3.0a17

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Notes

• The issue happens only when using a custom Mouse Cursor Sprite and setting the CursorMode to ForceSoftware. Using CursorMode.Auto or using the default mouse does not produce this issue
• The Main Camera uses the Pixel Perfect Component with the Windowbox attribute that controls the scaling of the camera. This option opens up the borders outside of the Camera affected range
• Opening the borders using the Camera Components Viewport Rect coordinates always produces the smearing effect even in the versions that the bug is not reproducible in. If this was done and the Pixel Perfect Camera Component was not active, activating it clears flags, and the issue is not visible (this only applies to the Stream versions that are not regressed)