Old Version of Firefox Website. Mozilla Foundation. Latest Version. Firefox 37.0.2. Old Versions. Some security software will need to be upgraded to a new version for each Firefox version update. Optional software bundled with security software may also need updating. Such software may not be essential for your security, but if outdated, it may interfere with the use of Firefox, or cause Firefox to crash.
Install and update How to install Firefox and keep it up to date • Firefox version 52.9.0esr was the last scheduled release for Windows XP and Windows Vista. No further security updates will be provided after August 2018. • This article will show you how to install Firefox on Linux. • Firefox automatically updates itself by default but you can always do a manual update. Learn how to update Firefox on Windows, Mac or Linux. • Learn how to find out what Firefox version you are using, to help troubleshoot a problem or just to know if Firefox is up to date.
• This article describes how to download and install Firefox on Windows. • How to switch to Firefox ESR as a workaround for issues with the newest version of Firefox. • This article describes how to remove the Firefox application from your computer and also how to remove the personal information that Firefox stores. • Downgrading usually doesn't solve Firefox problems. This article gives you links to old versions of Firefox and some alternatives to downgrading.
• This article explains how to download and install Firefox on a Mac. • On computers with processors older than Pentium 4, Firefox is no longer supported as of version 49 (Windows, Mac OS) or version 53 (Linux). • Learn about the automatic migration from 32-bit to 64-bit Firefox after a Firefox update and how to keep 32-bit Firefox on 64-bit Windows.
• Firefox and Thunderbird install Mozilla Maintenance Service to allow seamless background updates. Learn how it works and how to disable or remove it. • Not sure whether you're running 32-bit or 64-bit Firefox?
This article explains how to find out. • Firefox version 49 and above are no longer supported on Mac OS X 10.6, 10.7 and 10.8. Learn more about your options. • What to do if you spot fake notices claiming to contain an 'urgent' or 'critical' Firefox update. • How to create dedicated profiles for Firefox and Nightly to avoid profile corruption.
• Learn the risks of downgrading to an older version of Firefox on a shared profile. • Links to release notes for Firefox, Firefox for Android and Firefox for iOS.