"Colored Icons" setting doesn't always work. (I sometimes have to turn it off and back on again to get it to work.)
And most of the "conversation colors" in messenger don't work with this theme enabled.
I've only tried this dark theme for Facebook, and 1 other that had thousands of users.
I preferred this theme, despite its flaws. I hope they get fixed soon.
Thank you for this theme, pierOandMu.