: Offers a version history for Firefox, including portable versions that don't require a full installation . Installation Tips
For testing, legacy development, or specific compatibility needs, you can find the installers on the Mozilla FTP Archive : download old version of mozilla firefox 3.6
: If the FTP archive is difficult to navigate, OldVersion.com is a long-standing, reputable community resource for legacy software. Why Download 3.6 Today? : Offers a version history for Firefox, including
: Sites like OldVersion.com and FileHippo also host these files, but always verify the digital signature of the installer. Critical Risks & Limitations or specific compatibility needs
: It maintains compatibility with older XUL-based extensions that were disabled in later "Quantum" updates.
For safety, you should always prioritize official archives over third-party "mirror" sites, which may bundle the software with unwanted extras.