Small bug: lozenge numbers don't update with revert

This is in Glyphs 2 (haven’t tried in 3).
In a saved file, right click on a language, select all the missing glyphs and generate them. The lozenge with number of missing glyphs is replaced with a checkmark.
File > Revert to go back to the saved version (without the added glyphs).
The checkmark remains even though the added glyphs correctly go away. You can even right click and see the glyphs that can be added–the problem is just the lack of update of the lozenge indicator.