Thank you very much for the add-on. Now on to the issues:

1) With certain Firefox themes, when add-on is disabled it's pretty much invisible on the panel. Please fix. A sample theme https://addons.mozilla.org/en-US/firefox/addon/linen-light/

2) Please if possible implement a list of exceptions. To ease the pain please consider subdomains from the get go, i.e. when I whitelist abc.com, domain.abc.com gets whitelisted automatically

3) https://browser.geekbench.com/v5/cpu breaks with your add-on enabled and shows "Invalid Date". Please fix.

4) Breaks far too many websites for comfort. Looks like instead of changing the web browser TZ, it actually modifies certain JS code and it does so incorrectly in many cases. I have to uninstall it. Too much hassle.