RainbowTabs by Rainbow Scott

RainbowTabs is a Firefox extension that lets you color-code individual browser tabs for instant visual organization.

Right-click any tab or press Ctrl+Shift+C to assign a color — tabs reopen in colored Firefox containers so your color choices persist. Set up auto-rules to automatically color tabs when their URL matches a keyword (e.g. all "BaseAdministration" pages turn blue and get labeled "Principal"). AutoGroup mode automatically groups tabs from the same domain together. Sync your rules across browsers and machines by connecting with a device key from your RainbowTabs account — no passwords or OAuth required.

Built for anyone who juggles dozens of tabs and needs to know at a glance which is which, especially professionals who demo software live and need a visual safety net to avoid showing the wrong tab.