Rated 5 out of 5 stars

Love it. Would like this to be updated on Version 57. Guys please support Steva by donating on Pledgie. Thank you
https://pledgie.com/campaigns/35130

This review is for a previous version of the add-on (11.0.4.1). 

The Pledgie compaign I opened is only for my Thunderbird theme, but I have the feeling that in your comment you meant my FT DeepDark theme for Firefox. These are 2 different add-ons.

For the moment, my theme for Thunderbird works on the latest TB version which number is 52.5.0 (at least that's the latest one which is available where I am located).

Now concerning my theme for Firefox, for the moment I can't update it, because complete themes are not supported anymore by Firefox since the version 57. I m waiting for Mozilla to release the new theming system so I could see what's possible to do with it and to rebuild my theme according to it.