This is a new behavior that I'd like to prevent. I'll have several tabs open on a maximized Firefox. If I click on the taskbar icon to open a specific tab, firefox resizes itself to a position I arranged some time in the past on a closed tab. This occurs both when Firefox is the currently active (and maximized!) window and when Firefox is minimized, even if the tab I select was last maximized. This also occurs when I exit from fullscreen, with no taskbar selection at all. How can I configure Firefox to remain the exact size of the last open tab?