Tab Session Manager

Save and restore the state of windows and tabs. It also supports automatic saving and cloud sync.
– Save and restore windows and tabs
– Manage sessions with name and tags
– Auto save when window is closed
– Auto save at regular intervals
– Import and export sessions
– Compatibility with Chrome extension
– Cloud sync

Chrome version: https://chrome.google.com/webstore/detail/tab-session-manager/iaiomicjabeggjcfkbimgmglanimpnae
Firefox version: https://addons.mozilla.org/en-US/firefox/addon/tab-session-manager/