You appear to be using the on Firefox 60.0 on Windows 10.

For Windows t0, 11 then download the current Firefox 1145.0 Release or Firefox 140.5.0esr from below. https://www.firefox.com/download/all/desktop-release/ (Firefox 145.0 Release) https://www.firefox.com/download/all/desktop-esr/ (Firefox 140.4.0esr)

Or If this is with Firefox on your phone (Android or iPhone) then this likely means your Firefox version on the phone is too old as the web whatsapp site wants users to have Firefox 115 or newer.

https://support.mozilla.org/en-US/kb/update-latest-version-firefox-android https://support.mozilla.org/en-US/kb/firefox-available-iphone-or-ipad-my-language