You appear to be using Windows 7. The most current you can run on Windows 7 (and 8, 8.1) is Firefox 115.13.0esr as Firefox 116.0 and later requires Windows 10/11 to run. https://support.mozilla.org/en-US/kb/firefox-users-windows-7-8-and-81-moving-extended-support Firefox 115.13.0esr can be downloaded at https://www.mozilla.org/firefox/all/#product-desktop-esr Firefox 115.15.0esr in September is currently the last planned update for Fx 115 ESR unless Mozilla decides to extend support for Windows 7, 8, 8.1 and macOS 10.12, 10.13, 10.14 users.