Windows 10 warns me to use a "Microsoft-verified" app
Windows 10 may interrupt your Firefox install with a warning about "Microsoft-verified apps". Firefox is safe to install and use, so choose "install anyway".
Update Firefox to the latest release
Firefox automatically updates itself by default, but you can always do a manual update. Learn how to update Firefox on Windows, Mac, or Linux.
Firefox users on Windows 7, 8 and 8.1 moving to Extended Support Release
Firefox version 115 ESR will be the last supported release for Windows 7, 8 and 8.1.
Find what version of Firefox you are using
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.
How to install Firefox on Windows
This article describes how to download and install Firefox on Windows.
How to download and install Firefox on Mac
This article explains how to download and install Firefox on a Mac.
Install Firefox on Linux
This article describes how to download and install Firefox on Linux.
Firefox has ended support for Windows XP and Vista
Firefox version 52.9.0 ESR was the last supported release for Windows XP and Windows Vista. No further security updates will be provided for those systems.
I found a fake Firefox update
What to do if you spot fake notices claiming to contain an "urgent" or "critical" Firefox update.
Windows in S mode won't let me install Firefox
You cannot install Firefox from Mozilla or from the Microsoft Store on Windows in S mode. You must first switch out of S mode. Learn more.
Firefox users on macOS 10.12, 10.13 and 10.14 moving to Extended Support Release
Firefox version 115 ESR will be the last supported release for macOS 10.12, 10.13 and 10.14
Uninstall Firefox from your computer
This article describes how to uninstall the Firefox application from your computer and also how to remove the personal information that Firefox stores.
Download Firefox on Windows from the Microsoft Store
The "Mozilla Firefox" app is available from the Microsoft Store for Windows 10 and Windows 11. Learn how to install it.
Switch to Firefox Extended Support Release (ESR) for personal use
How to switch to Firefox ESR as a workaround for issues with the newest version of Firefox.
Install an older version of Firefox
Downgrading to a previous Firefox version doesn't solve most problems. This article links to older versions and provides some alternatives.
How do I tell if I have the 32-bit or 64-bit Firefox?
Not sure whether you're running 32-bit or 64-bit Firefox on your Windows or Linux computer? This article explains how to find out.
Recover user data missing after Firefox update
If your bookmarks, passwords, preference settings and other data are missing, it may be available in another Firefox profile. Learn more.
What is the Mozilla Maintenance Service?
Firefox and Thunderbird install Mozilla Maintenance Service to allow seamless background updates. Learn how it works and how to disable or remove it.
Firefox Mac OS X 10.9, 10.10 and 10.11 users move to Extended Support Release
Firefox 78 was the last supported version for Mac OS X 10.9, 10.10 and 10.11. Users were moved to Firefox Extended Support Release (ESR).
Will Firefox version 100 work on Windows 7?
On Windows 7, Microsoft update KB4474419 is needed to install Firefox 100 or above without any issues. Learn more.
Firefox release notes - What's new and known issues
Links to Firefox release notes for Desktop, Android and iOS.