Millions of users use Mozilla Firefox as a private browser to navigate various websites, emails, downloads, etc. It may take a long time to open, so you must focus on the few troubleshooting steps mentioned below. ● Delete recent history ● Turn on Start-up Preferences ● Delete duplicate files restore on sessions ● Update Plugins in Mozilla Firefox ● Check Antivirus software interference After following the above steps, you can resolve it successfully. If it is not decided, you must call Mozilla Firefox customer care to rectify it. Read more: - Fix Firefox Takes a Long Time to Startup | How to Fix Mozilla Firefox Keeps Asking for the Master Password