Mozilla does not host these old versions on their main website ( mozilla.org ). They use a dedicated archive. Here is the safe method to download. Mozilla officially maintains an FTP server at archive.mozilla.org . This is the safest source (No viruses, no fake installers).
In the fast-paced world of web browsers, staying updated is typically the golden rule for security and performance. However, for a niche group of IT professionals, businesses, and vintage tech enthusiasts, the latest isn't always the greatest.
Disclaimer: Mozilla, Firefox, and the Firefox logo are trademarks of the Mozilla Foundation. This article is for educational and archival purposes only. Download Firefox 12-51 52 Esr
The ESR (Extended Support Release) is designed for organizations. While standard Firefox 52 received security updates only until September 2017, . For Windows XP users, Mozilla extended this specifically to 52.9.0 ESR .
However, if you are a museum curator running a digital kiosk, an engineer connecting to a 2010 medical device, or a retro gamer trying to open a Flash game from an old hard drive: Mozilla does not host these old versions on
Always download directly from archive.mozilla.org . Never trust third-party "old version" websites, as they are notorious for bundling malware.
Posted by Legacy Software Team | Updated: October 2024 Mozilla officially maintains an FTP server at archive
If you install Firefox 52 ESR, you must immediately disable automatic updates. Otherwise, it will auto-upgrade to Firefox 60 ESR (which drops NPAPI support and will break your legacy plugins).