It's really useful!

it's doing what it's supposed to do

unstable with deezer.com on firefox 123 win64

Very useful add

does nothing in the latest few versions of firefox

If this add-on has a UI, it completely escapes me.

great experience

The option to change the global user agent "Apply (container or window)" doesn't work even on the website "webbrowsertools.com". Tested on Firefox 121.0.

Domain whitelist / blacklist does NOT work

when your bank has stupid expectations of updates switch your agent. Else run a virtual machine

Great at bypassing browser discrimination

Does nothing with Firefox 120/Ubuntu