Firefox Developer 92.0b4 has incorrect UserAgent

I was getting errors accessing some sites (Google Drive for one) where I was being redirected to a support page telling me to update my browser. I use FF Dev as my default browser, and that’s like two steps away from bleeding edge, so I knew something was wrong.

Attached screenshot shows the “About Firefox Developer Edition” modal displaying the version number, over the console showing the results of navigator.userAgent as Firefox/65.0!

Screen Shot 2021-08-16 at 4.30.13 PM

Sites should really be doing Feature Detection and not UA sniffing, but still!

92.0b5 on Windows seems fine. Can you confirm it’s not something in about:config – – or a substitution made by an extension.

Strangely, the problem was not resolved after restarting the browser, but after a reboot it is announcing the correct UA.