Tilemaps messed up with 2021 upgrade

Hello,

I'm wondering if i'm the only one. When i try to upgrade from the last Unity 2020 to current 2021 version, some of my tilemaps get messed up, the rotation of the tiles seems to be canceled. Is this a known issue? Is there a general feedback about the latest Unity thread? I couldn't find one.

Thanks

 

Didn't try the upgrade but seen something similar before with broken tilemap on prefabs. Did you try re-importing them?

 

Hello,

Reimporting didn't help. It is the weirdest thing as when i open the tile palette, everything seems fine at first but about a few seconds later, they appear with the same result as the tilemap, the rotation i have applied to get four corners disapears and they revert back to their original transform.