I did search the forum for a similar subject, but maybe it was already discussed somewhere I couldn't find...
Anyway: I found by accident about a Qt change for future releases:
I'm no developer and can't say how this may affect FreeCAD releases in the future.
Actually, I'd like to ask that to the developers, if would be the case to plan future releases with a different base (GTK, Kivy, WxWidgets...?) or if this changes won't cause trouble to FreeCAD.
I'm guessing that Qt it's used only for creation of the program interface...