compatible

Think you have the most up todate Fx 115

https://support.mozilla.org/en-US/kb/firefox-users-windows-7-8-and-81-moving-extended-support

need to update my Mozilla

Firefox 116.0 and later requires Windows 10, 11 to run (a current Linux distro in dual boot is an alternative) as the most current you can run is the older Firefox 115 ESR currently at Fx 115.41.0esr and is planned for updates till March 2027 unless it gets extended yet again.

The Firefox 115 ESR is based on the old Firefox 115.0 Release but with security/stability fixes since so some websites may think you are using the old Firefox 115 Release. Or some sites may not work right as site was made for to work on newer Firefox versions. At least Mozilla is still supporting the EOL Windows 7, 8, 8.1 and macOS 10.12, 10.13, 10.14 unlike with Chrome/Chromium based browsers dropping support back in Jan/Feb 2023.

Bonsoir

For information Firefox release calendar https://whattrainisitnow.com/calendar https://whattrainisitnow.com/release/?version=esr

To complement, these discussions, https://connect.mozilla.org/t5/discussions/firefox-115-41-0-esr-fails-to-display-some-web-pages-correctly/td-p/138971 - https://connect.mozilla.org/t5/firefox-labs/webseite-sein-monaten-nicht-erreichbar/td-p/136998