Allow all windows to be docked
Of the windows listed in the "Display" menu, three of them (Palette, Navigator, and MuseScore Connect) come up docked in the main window. You can move them around, or detach them into separate windows. But the other three (Play Panel, Mixer, and Synthesizer) are always in separate windows and, as far as I can tell, cannot be docked.
Could you make all of the windows dockable? For example, I'd really like to be able to dock the Mixer in the main window. That would make it a lot more convenient when I want to listen to individual tracks.