This addon works to significant degree, but there is a problem with the preferences screen.

The preferences screen for this addon is not great. I could not figure how to set the colors. I managed to make some changes, but I could not figure out the process for setting them.

The random color setting works well, except the colors are awful bright, clashing with dark themes.

Excellent extension. It helps me to identify when I'm on a production, staging or local development when building website. However One big point that could really be improved, is the possibility to add multiple URLs in the input field or having templates of colors.

I want all my production website on red, staging yellow etc.. And it take a long amount of time to configure each of them.

Thanks for your work Max!

Gives you a vivaldi look for Firefox 58.0.2 but you can't use firefox theme with this addon

I love the way you colors the tabs. But you also paint the whole background. As many people I use a lot of themes for background which I rotate, and this I can't enjoy anymore as I use your add-on.
Would you consider an option to only color the tab, not the whole theme?

Works perfectly to let you see which tab is active.
All tabs as well as the bookmarks toolbar are always easily legible.
Website icons retain their colors & remain easy to see.
As far as I can tell, this extension completely overrides themes.
Enhancements I'd like:
Nonactive tabs retain their active color, or better, a faded-back version of it.
User-selected color palette.