Firefox 78.11 is the latest extended support release version, Firefox 89.0.1 is the latest regular version. See also
older Mac OS users switched to Firefox ESR.
Originally Posted by
Carrier
What is it sending and where may it be found?
Right click on a page & select Inspect, select the Network tab & reload the page. Click on one of the requests then in the right hand pane scroll down to User-Agent.