Dark Reader - Reduce eye strain in your browser with this extension that provides a dark theme for browsing.

Tabs Outliner - Next Generation Session, Windows, Tabs Manager and a TooManyTabs Solution That Really Works.

Night Eye - Night Eye is a browser extension that enables dark mode on any website you visit. It does not ruin your browsing experience by simply inverting images.

Tree Style Tab - Tree Style Tab is an all-in-one Firefox extension that provides ability in order to operate tabs as a tree.

Dark Mode - A global dark theme for the web

OneTab - Whenever you find yourself with too many tabs, click the OneTab icon to convert all of your tabs into a list. When you need to access the tabs again, you can either restore them individually or all at once.