Steps to  fix Mozilla Firefox Issues or problems :

• Start your computer again.-Occasionally, difficulties can be resolved by restarting your computer and then relaunching Firefox.
• Clear your cache and cookies.-Clearing Firefox's cookies and cache can fix a lot of problems with web page loading:
• In Troubleshoot Mode, restart Firefox.
• Reinstall Firefox if necessary.-From mozilla.org, download and save the installer for the most recent official version of Firefox. Close Firefox (if it's open): Select Exit from the Firefox menu. Make a note of where the Mozilla Firefox program folder is located (right-click the Firefox desktop icon, select Properties from the context menu, and then click the Shortcut tab) because there may be remaining files and folders that need to be removed for a clean reinstallation.
• Firefox should be uninstalled from your machine. Delete the Firefox application folder, which is often located in one of the following locations: Use the software you obtained previously to reinstall Firefox - see How to install Firefox on Windows for details. Restart Firefox.
• Make a new profile in Firefox.

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