User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:2.0) Gecko/20110321 Firefox/4.0 Build Identifier: Mozilla/5.0 (X11; Linux x86_64; rv:2.0) Gecko/20110321 Firefox/4.0 When download manager is open and user closes the last window (therefore closing the last tab too), the closed tab is restored when user opens a new window. Reproducible: Always Steps to Reproduce: 1. Open one window with one tab in it. Load any website. 2. Open download manager 3. Close the window 4. Open a new window Actual Results: Website from closed one is restored in the new window. Also when firefox is started with URL given via command line, it opens website it was asked to open AND restores one from the closed window (in two tabs). Expected Results: Start home page. In the second case: only URL from command line should be opened. This does not happen if the last tab is closed directly (not by closing whole window) or when the last tab has nothing loaded in it.
Additional info: The download manager should be downloading something to prevent it from closing when the last window is closed. A moment ago my friend has reported that the same situation occurs with multiple tabs.
I can confirm this bug. Build Identifier: Mozilla/5.0 (X11; Linux i686; rv:2.0) Gecko/20110321 Firefox/4.0