Aside from the white and black lists, this extension also has a list of domains where the UA should never be spoofed. It's never stated that it exists, and I found it out only when I accidentally opened the settings. This list includes domains I was using this extension for, which means that my UA wasn't actually spoofed there. 1/5, many thanks for a privacy leakage for no apparent reason.

it is difficult to master - you need a simple GUI option, where each site offers its own identifier, and not offer to write in a scripting language.
and of course the fox starts using the processor from 1.5% to 15%.

The modified browser profile does not pass Cloudflare's validation. https://webbrowsertools.com/ip address/

With extension enabled all the sites that use Cloudflare are don't load. Which makes this extension pretty much useless. I hope this issue get fixed then i will change my review.
Edit: Another review reminded me that it "makes the CPU go nuts every 30 seconds!"

This bugs websites that use Cloudflare DDoS protection in the default settings. Funny that their own official website uses Cloudflare protection, so there is probably a workaround but I prefer to just disable it.

A bit unintuitive, but does the job. Bing chat here I come.

Little bit unintuative. Automatically starts only in containers. Doesn't have random UA switcher.

This plugin is either a completely unintuitive piece of crap or it just plainly doesn't work in firefox 113

Does exactly what I need it to do. I love that I can set the user agent per site. I can save and export my configuration or I can change the user-agent string ad-hoc.

This is a great, simple, and robust application. 5-stars for my needs.
Several shortcomings: The user agents are not that up-to-date. currently, i am using fierfox 112 but the add-on shows a user agent up to firefox 108. not a big deal; i can edit that manually but i preferred if the add-on automatically updated that info.
I'd also like there to be a mode for the extension to auto-apply the most used user agents out there on the web.