Reproduction steps:
1. Open the attached “Unity 6 HDRP.zip” project
2. Open the “test sprite” Scene (Assets > #)
3. Select the ‘Image' GameObject from the Hierarchy (Canvas > Image)
4. Observe the ‘Source Image’ property in the Inspector
5. Enter the Play mode
6. Observe the ‘Source Image’ property in the Inspector again

Expected result: The “0005_Character 1” Sprite is still referenced in the ‘Source Image’ property
Actual result: The ‘Source Image’ property is set to None

Reproducible with: 2021.3.46f1, 2022.3.54f1, 6000.0.30f1, 6000.1.0a7

Reproducible on: Windows 11
Not reproducible on: no other environment tested

Notes:
- Does not reproduce in the Player
- Could only reproduce with the “0005_Character 1” Sprite