Not working at all properly in Quantum Firefox 58. It was GREAT in pre Quantum Firefox. I loved how it gave different colors to different tabs, because with this simple feature, I could much more easily see, & manage, working with lots of multiple open tabs.
In Quantum 58, it doesn't work that way at all. It just creates a weird color spread collage, which all tabs get uniformly. It sits there, and does that & nothing else. The homepage to alter settings is confusing, and doesn't seem to help at all. In the old preQuantum version, it would simply give a different pleasant color to each tab top header, so it was easy to find different tabs, and organize them. This version is totally different, and careless and distracting, unsettling, and dreary. I've disabled this, because it is nothing like the old ColorfulTabs in preQuantum Firefox. If it gets fixed, and works like it used to, I'll be happy to enable it & use it all the time. But this version, no, it creates more visual clutter, rather than organizing my tabs properly, so it does the OPPOSITE of what I'm looking for.