If Firefox seems to hang randomly and not after a specific action (for example, downloading a file or quitting Firefox), try the solutions in this section. Create a new places database If hangs are periodic, it may be caused by a corrupted places database. Information: The "places" files store the annotations, bookmarks, favorite icons, input history, keywords, and browsing history (a record of visited pages). To create a new places database, do the following: Warning: This will clear your browsing history and remove bookmarks of the day. Open your profile folder: Click the menu button Fx89menuButton, click Help and select More Troubleshooting Information. The Troubleshooting Information tab will open. Under the Application Basics section next to Profile Folder, click Open Folder . Your profile folder will open. Note: If you are unable to open or use Firefox, follow the instructions in Finding your profile without opening Firefox. Click the Firefox menu Fx89menuButton and select Exit. Wait until Firefox has completely quit. In the Firefox profile folder, find and rename the files places.sqlite to places.sqlite.old and places.sqlite-journal to places.sqlite-journal.old (if it exists). To rename a file, right-click on it and select rename from the menu. Then add .old to the end of its name. Finally, reopen Firefox. When Firefox reopens it will create a new places database. Your browsing history will be lost but Firefox will automatically import your bookmarks from the most recent backup file. Turn off hardware acceleration With some graphics card and graphics driver setups, Firefox may hang when using hardware acceleration. You can try turning off hardware acceleration to see if it fixes the problem. Click the menu button Fx89menuButton and select Settings. Select the General panel. Under Performance, uncheck Use recommended performance settings. Additional settings will be displayed. Fx55Performance-disableHWA Uncheck Use hardware acceleration when available. Click the Firefox menu Fx89menuButton and select Exit. Start Firefox the way you normally do. If the problem is no longer happening, then hardware acceleration was likely the cause. You can try updating your graphics drivers to see if that fixes it or simply run without hardware acceleration. Change the PAC implementation If you're using a proxy auto-config file (PAC), Firefox may hang when you attempt to load sites that don't exist or that you haven't opened recently. To determine if you use an automatic proxy configuration file: Click the menu button Fx89menuButton and select Settings. In the General panel, go down to the Network Settings section. Click Settings…. The Connection Settings dialog appears. If Automatic proxy configuration URL is selected, you are using an automatic proxy configuration file. Do not disable this setting, which will prevent you from accessing the Internet. Instead, provide this workaround to your network administrator. Click Cancel. Regards, Rachel Gomez