ProxyCompass
Open Tabs Next to Current
Tabs Outliner
Tab Utilities
Tree Style Tab
Duplicate Tabs Closer
Tab Tally
Adguard AdBlocker
Tab Stash
Firefox Multi-account Containers
Lightbeam for Firefox
island
App Cloner
Tree Style Tab
Session Box
AllAccounts
Simple Tab Groups
Open Tabs Next to CurrentTabs Outliner - Next Generation Session, Windows, Tabs Manager and a TooManyTabs Solution That Really Works.
Lightbeam for Firefox - Mozilla is the not-for-profit behind the lightning fast Firefox browser. We put people over profit to give everyone more power online.
Tab Utilities - Tab Utilities is an ultimate tab solution for all kind of users who want to manage their tab, create multiple session and search for new tabs, etc.
island - a free and opensource alternative to parellel space
Tree Style Tab - Tree Style Tab is an all-in-one Firefox extension that provides ability in order to operate tabs as a tree.
App Cloner - Clone your Android apps so you can use multiple logins.