The curve widget in the redo popup would sent an undo push which it
shouldn't really. Since 1bde901bf2 such undo pushes will lead to
clearing of the last operation data, which is exactly what the redo
popup displays.
Buttons in operator redo UIs shouldn't send undo pushes. 179169d6c7
disabled them for the "Adjust Last Operation" panel, but not for this
redo popup. In fact there was other code to disable undo for these
buttons, but 2d2f23de10 put this into a wrongly scoped conditional
branch, so it was only executed on the first full redraw.
We can revert 179169d6c7 too now (confirmed already), but I'll do that
separately and not in the release branch.
Confirmed that the following related issues are all (still) fixed with
this:
- #55348
- #134505
- #135655
Pull Request: https://projects.blender.org/blender/blender/pulls/135730
df4345dbaa