Rated 5 out of 5 stars
I like your addon, and it's very good it's e10s compatible!
However, there's one feature I would very much like to have — Multiple Tab Handler (https://addons.mozilla.org/en-US/firefox/addon/multiple-tab-handler/ ) compatibility. Personally, I prefer not to have all tabs colored but only the ones I need, e.g. the tabs I've already read.
I would like to be able to choose multiple tabs and highlight them with the same color using a keyboard shortcut or a ColourfulTabs context menu.
As of now, when several tabs are selected with Multiple Tab Handler, there is no ColourfulTabs context menu, and when I use the keyboard shortcut, only the current tab is colored, not all selected tabs.