This is a great add-on I've been using for several years as a premium user. That said, it seems the development of the Firefox version halted or at least slowed down. The last version in Firefox is from Nov 8 2017 vs July 2018 for Chrome. I've noticed several bugs and things that do not work anymore. Judging by the ratings in both platforms it seems Chrome users are getting a better experience. This is unfortunate for me, as I like Firefox better than Chrome. My rating is in good faith for now but if they let the Firefox version die I will drop my subscription.