chore : remove the mac-specific workaround for fullscreen (okay if the mac version is compiled with gtk > 4.14 and the mac os version is already using gtk 4.14 anyway)
improv : Do not save the size of the window if the window is maximized. This makes closing a rnote application in maximized form remember the last window size when dragging it down rather than have the same size between maximized and non maximized state on the next launch.