Doesn't work with some national domains such as amazon.pl

For me, there;s one issue I have with this add on, and that's the symbol I choose keeps changing it back to a the briefcase. I think it is because of your add on, it might be because of Firefox Multi-Account Containers, but I wish there was a way to keep the symbol from changing.

Seems to do its job but (as we could expect) also blocks embedded Twitch streams (in my case lolesport.com), would be nice to add an option to disable restrictions on chosen websites.

It's great, but please add CurseForge: https://www.curseforge.com/

Does its job really well on Amazon owned sites but does not include wholefoods.co.uk.

Seems to provide the same functionality as Facebook Container does, but for Amazon domains. Exactly what I was looking for.
I can't speak to the security of the add-on itself. With so few users and reviews at this point I guess you're putting your faith in the developer.