Its really good but my operating system was detected on https://ipleak.net/

It cool and handy

Does it's job well. Now most sites think this pc is not a Linux machine. However. Permanently changing the user agent to something else. Still could enable sites to identify you. Only thing is, the information you provide is not correct.

Very functional addon. I'm trying this over the other top downloaded user-agent addon by Schlarb due to this one being recommended by Mozilla, but I still think the UI is kinda clunky. Needs faster access to UA switching for specific domains other than black/whitelisting them on the options page.

Very nice..

UI is clumsy but fairly usable. Otherwise, works fine.

What I and others would really like is a much smaller button. It takes up way too much room on the URL Bar in Firefox .. Or at least, give us an easy way to minimize the UI Button after we select a User Agent to use. Otherwise, this is a pretty add on. I like that the developer continues to update the agent strings. Youtube has changed the way they do things and you need to allow Ads in order to see Notifications or make a Comment on a Video om Youtube .... Luckily, not a big deal, as the ads are short and you can skip them.

Can you spoof UserAgent from header ?
Check on https://browserspy.dk/useragent.php
Not working on first visit.

Just some constructive criticism: The headlined feature of UA randomization is not explained well and could be implemented better. Having additional functionality that is not streamlined is always better than not having it at all, so I can't complain much :)