Hello, I am using Firefox with Windows Vista. It is really slow and glitchy. Can I change it? Do you need a list of the add-ons I have? This was a reply, but it didn't answer the question. fredmcd-hotmail (Mozilla Support Contributor) posted a new reply in Firefox on 15-04-2017 05:59 AM : Re: Firefox with Windows Vista is really slow and glitchy. Can I change it? As of Firefox 53 in March 2017, WinXP and Vista won't be supported any longer. http://www.ghacks.net/2016/09/27/firefox-53-no-support-for-windows-xp-or-vista/ https://support.mozilla.org/t5/Install-and-Update/Important-Firefox-is-ending-support-for-Windows-XP-and-Vista/ta-p/31270 You can install the Firefox ESR 52 version which will get security updates into early 2018, to get "more time" using Firefox. Firefox Extended Support Release https://www.mozilla.org/en-US/firefox/organizations/ https://www.mozilla.org/en-US/firefox/organizations/notes/ https://www.mozilla.org/en-US/firefox/organizations/system-requirements/