I've been using Firefox in Windows for years as my default browser. Suddenly tonight, Microsoft Edge became my default. When I go into Windows Settings and try to change back to Firefox, Windows offers me only Microsoft browsers as alternatives (or offers to let me into the Microsoft Store): Windows Edge or Internet Explorer. The Control Panel / Settings page "Set Default Apps" is the only way that I know that Windows lets users set default browsers, but it suddenly seems to be restricting me to only MS browsers. Firefox works normally in every other way, but warns me now every time I launch it that I have a different default browser. When I click the button in the warning (or in Firefox's Tools / Settings) I just get put back to the Windows "Set Default Apps" page, which, again, only lets me choose Microsoft browsers. What could have happened? I haven't altered my Firefox configuration or installed extensions or plug-ins in a long time. If I uninstall & reinnstall Firefox, will I lose my many configuration & interface settings and will I have to reinstall all my extensions -- or will the reinstalled Firefox remember its existing configuration? Or would that probably not help at all. I'm very computer-savvy, but have run out of ideas. Can you help?? DJL