Undoing Weight Paint While Bones Are Moved in Skinning Editor Breaks Mesh (2021.3.16f1)

[Unrighteouss]

Hello,

I noticed this while messing around today. If you undo (ctrl+z) any weight paint changes while bones are moved in the skinning editor, the mesh is permanently moved to a different location.

Here is the default pose of this limb:

Here I moved the orange bone:

Here I weight painted the orange section all purple:

So far so good… but then if I undo the changes I just made, this happens:

The mesh doesn’t revert back to where it was before.

This is what it looks like after pressing “Restore Pose:”

Reproducing this shouldn’t be difficult, it happens 100% of the time when I do it. I was using the weight brush and 100 Hardness when I was testing this.

Unity 2021.3.16f1
2D Animation 7.0.9
2D PSD Importer 6.0.6

[Ted_Wikman]

Thank you for highlighting this issue.
We have a bug report for this, and you can follow the progress here:

Unity IssueTracker - [2D] Using undo in the Skinning Editor after moving...