Firefox version 115 will be the last to support Windows 7, 8, and 8.1. Users of these operating systems must upgrade to Windows 10 or newer to continue receiving updates after February 2026. Mozilla has decided to discontinue support for these older versions of Windows due to the cessation of security updates from Microsoft since January 2023 and the associated costs and risks. Other major browsers have also stopped supporting these outdated systems. Users unable to upgrade can consider switching to a Linux-based operating system, which often comes with Firefox pre-installed. Firefox is favored in the Linux community for its open-source nature and efficient memory usage compared to browsers based on Google's Chromium codebase.