Reproduction steps:
1. Open the user-attached project
2. Open the Sprite Sheet named “item sprite atlas” inside Assets > Inventory > Item_Sprites using Sprite Editor
3. Try adding a new sprite tile by selecting its outline
4. Observe the Sprite Editor window

Expected result: A new Sprite Tile is created
Actual result: The last created Sprite Tile is selected

Reproducible with: 2021.3.36f1, 2022.3.21f1, 2023.2.13f1, 6000.0.0b11

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

Notes:
- Workarounds:
a. Duplicate the Sprite Sheet
b. Rename the Sprite Sheet (if you rename it again back to the original, the bug reproduces again)
(also, if you name another Sprite Sheet as “item sprite atlas” the bug reproduces on it)
- Not reproducible in an empty project