If Firefox won't open windows 10 issue, shows up to you as well then you are not alone. Certain Firefox problems can be solved by performing a clean reinstall. This means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location. You can simply download or update Firefox.

Visit: https://contactforhelp.com/blog/mozilla-firefox-not-responding-on-windows-or-wont-open-on-mac/