Oh, absolutely. It seemed that I would have to say goodbye to Tab Center with 57 and was very unhappy with it, but thankfully it turned out that I was able to make it even better than before. userChrome.css rocks :)
I've been running the side-bar version of tab center with this userChrome.css fix but the best I can say about it is that it's "alright". The window close/max/min buttons are just not positioned very well on macOS.
Also, if you hide the sidebar header I think you run the risk of accidentally opening the bookmarks sidebar and being unable to get back to your tabs.
https://dosowisko.net/Screenshot_20171030_203716.png https://dosowisko.net/Screenshot_20171030_203804.png