Are you sure the AppImage had the issue in the first place? If you revert to defaults:
Code: Select all
p = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Bitmaps/Theme")
And re-start FreeCAD, AppImage has the issue? If yes, you are likely using a custom desktop icon theme? What happens if you revert that to defaults?
P.S. Note that FreeCAD must not crash on close, for the changes to have an effect. Only have one instance of FreeCAD running, when applying the changes and doing tests.