Updated the extension to latest version and got confused if I switched to Chrome somehow - same handicapped UI that the extensions has there :/ No way to see what exactly has been blocked or what could be blocked (open block-able items) - instead I have a "nice and truly needed" (not!) feature of sharing the number of items blocked in the social media sites! A feature that is apparently so important that it's placed so that You will hit it by accident most likely :/ Switched back to old version almost immediately - as I haven't switched to Firefox 57 yet.

Have been using and enjoining the extension for many years though - thanks for the authors :) I just hoped that at least some extensions ported to WebExtensions would remain usable :/ All-in-all, blame goes to Mozilla I suppose.