User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US) AppleWebKit/532.0 (KHTML, like Gecko) Chrome/3.0.197.0 Safari/532.0 Build Identifier: There are counterintuitive difference between closing a window with multiple tabs and closing the whole application. If I just close one window with multiple tabs, even if it is the only browser window, it warns me that I have multiple tabs open but does not offer to save them. If I use the File/Exit menu it offers "save and quit". It took me a while to figure out how what GUI operations led to each exit behaviour. File/exit is not by its placement or its wording obvious to a user that it will exit the whole app rather than just the browser. Some extensions such as Chatzilla run in their own window and are not intuitively part of the browser. This makes the difference between close window and File/Exit even more confusing. Chatzilla is my only IRC client but I use several browsers. If I accidentally open a browser tab from Chatzilla it will restore my previous session. If I'm using another browser I want to close the Firefox browser and save the session but leave Chatzilla operating. If I close the browser window I have no offer to save the session, but if I go to File/Quit I also lose my Chatzilla! Reproducible: Always Expected Results: Closing a window with multiple tabs should behave to the user more like File/Exit, especially as far as saving sessions, and especially when it is the only or last open window. The menu item text and the dialogs on closing the app and closing a window with multiple tabs should be more informative so the user can see the operations are not equivalent.