The window can reach sizes at which the "resize" corner is no longer shown

The "resize" corner (Mac only, both Linux and Windows windows can be resized at any corner and side) of the application window can easily become hidden as the window length surpasses the screen size (for instance, by showing a number of palettes).
(To reach a normal size again, the user can usually use the "+" button, but this might not always be a solution and is nevertheless not a very obvious one.)