Install an older version of Firefox

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Often when there is a problem with a Firefox update, people look for a way to go back to the previous version. That usually doesn't solve the problem and will make your computer and information vulnerable to attack. This article gives you some alternatives to downgrading and links to old versions of Firefox if you do choose to downgrade.

Installing a previous version doesn't fix most problems

Problems with an update are generally not caused by the new version of Firefox, but rather the update process. Installing a previous version will not help in most cases. Instead, see:

Note: Other problems can be solved with the Refresh Firefox feature. It restores Firefox to its default state while saving your essential information.

Ensure all security and security related software is fully updated. 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 Such software may not be essential for your security, but if outdated, it may interfere with the use of Firefox, or cause Firefox to crash.

I still want to downgrade — where can I get the previous version?

Although Mozilla has a website with old versions of Firefox for testing purposes, it is not recommended that you use anything but the latest version.
Warning: Using old versions of Firefox poses a significant security risk.

By default, different versions of Firefox will use the same user profile data. Installing an older version of Firefox after using Firefox version 55 or above can cause problems such as error messages, breakage in portions of Firefox and issues with some websites. You should either create a new profile or else refresh Firefox after installing the older version.

  • Windows XP SP2 users: The last Firefox installer previous to Firefox 49 that can be executed on XP SP2 systems is Firefox 43.0.1 (US English).
Important: By default, Firefox is set to automatically update itself. If you install an older version of Firefox, you'll need to change your update settings to prevent the latest Firefox version from being reinstalled. See Advanced panel - Accessibility, browsing, network, updates, and other advanced settings in Firefox for details.

If you can't use the latest version of Firefox, instead of installing an older version and changing your update settings, we recommend that you use the latest version of another browser:

Help us make Firefox better

If the latest version of Firefox is causing problems for you or you just don't like something about it, please give us feedback about it here:

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