THIS ADDON IS NOT INTENDED FOR AUTO-SAVING OF SESSIONS! Save sessions as bookmarks and access them across devices Using Session Sync you can save sessions as bookmarks. Use the rich user interface for session management: create, restore, open, edit or delete sessions/bookmarks or add new tabs to a certain session. Why save sessions as bookmarks? - all the data saved will be there no matter what addon you may use in the feature - when using the url bar, Firefox will automatically suggest links based on your bookmarks - easy access/edit/backup and then restore saved data using the integrated Bookmark Manager (even on smartphone / tablet) even if the addon is not installed Shortcut keys - CTRL+SHIFT+F - open the Widget UI - CTRL+SHIFT+V - open the Tab View - CTRL+SHIFT+U - open the Window View - Shortcuts configuration can be changed from configuration (Firefox 60 and up, lower version do not offer the API required) The sync functionality works with any bookmark synchronization service like:

Firefox Sync Account (recommended)
EverSync

Session Sync will automatically detect new updates and display the updated sessions list across multiple machines. General features - active session management (move around tabs) - advanced bookmark management - session restore with lazy-loading - session auto-saving (not backed by Bookmarks) - history list - session can be saved later as classic bookmark sessions - private windows are ignored by auto-save - auto-saving is only intended as a nice addition and is not full-featured (please look for other addons for complete auto-saving support) - session filtering (search text) and sorting by name/position/date - advanced drag-n-drop UI with fluid animations - advance UI scaling for individual UI areas (session list, bookmark list, session header and toolbar) - 3 working modes: Panel, Tab View, Window View - many other customization Required permission explained:

Read and modify bookmarks - required for storing sessions as bookmarks as well as interacting with them
Input data to the clipboard - required for right-click menu in order to copy bookmark title/URL
Access browser tabs - required in order to be able to read/save browsing session information. (This provides only tab properties and not actual browsing content)
Store unlimited amount of client-side data - Required for addon Settings, favicon caching, auto-saved history as well as additional information for sessions

All data is stored local and/or is synced on your Firefox Account (bookmarks).