Firefox 78 End of Life

Support dates and upgrade guidance — rebuilt from live data.

End of Life

Firefox 78 reached end of life on 2 Nov 2021. It no longer receives security fixes.

1,741 days without security patches

Recommended action: upgrade to Firefox 153.

Check your versionfirefox --version

Support timeline

Official dates from the Firefox release process.

Milestone	Date	Status
Initial release	30 Jun 2020	—
End of life	2 Nov 2021	4.8 years ago
Latest release	78.15.0 · 5 Oct 2021	final

Where to go from 78

Recommended target: Firefox 153.

The newest actively supported branch is Firefox 153 (latest release 153.0.3).

Frequently asked questions

Is Firefox 78 still safe to use?

Firefox 78 reached end of life on 2 Nov 2021, 1,741 days ago, and is no longer covered by standard support. Running it means no guaranteed security fixes.

Can I still download Firefox 78?

Yes — the final release (78.15.0) generally remains available from vendor archives and OS package mirrors, but installing it means running software with known, unpatched vulnerabilities.

What should I upgrade Firefox 78 to?

Upgrade to Firefox 153, the newest actively supported branch.

Firefox 78 End of Life

Support timeline

Where to go from 78

Frequently asked questions

All Firefox versions