After setting window height to max by dragging the upper edge up to top of screen, Firefox does not reset window height on exit.

I have a large screen and seldom use a window of full height other when shopping online. After setting Firefox window height to max by dragging the upper edge up to top of screen, Firefox does not reset window height on exit. I seldom remember to set window to full screen and back to overlapped windows before exiting to accomplish the reset. This means I must reset the height of Firefox manually the next use as I do many operations where I have several windows open with a portion of each showing. this allows me to switch windows without leaving the mouse (or waiting for the status bar to reappear so I can select the desired window) System is Windows 7-64 bit.