Tab Session Manager作者： sienori

Save and restore the state of windows and tabs. It also supports automatic saving.

• 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

Chrome version:
https://chrome.google.com/webstore/detail/tab-session-manager/iaiomicjabeggjcfkbimgmglanimpnae

USERS:

• Since updating to version 3.0.0, there is a problem that the session list can not be opened. Please see here for solutions. https://github.com/sienori/Tab-Session-Manager/wiki/IndexedDB-Error
• Vote on Mozilla website for APIs/bug fixes needed by session managers, so they can be better. https://github.com/sienori/Tab-Session-Manager/issues/364

Version 4.5.0

• Add keyboard shortcut (firefox 60)
  • You can customize it on the options page
• Improve accessibility of option page
  • Solved the problem that checkbox and radio button could not be selected with keyboard

Version 4.4.0

• Added function to add current window to a session
• Improved visibility of session menu
  • Added section label
• Added function to restore deleted tabs and windows from session
• Changed not to display delete button when there is only one window or tab in the session

Version 4.3.0

• Added option to enable debug mode

Version 4.2.0

• Improved behavior of Auto save when window was closed
  
  • It divided into window closed and browser exited
  • Fixed problem that only one window could be restored with option of "restore previous session at startup"
• Added option to use "discarded" property for lazy loading (only Firefox 63 or later)
  
  • Improve performance when opening tabs
• Fixed problem that increased memory usage when restoring session or closing a large number of tabs
• Fixed problem that tabs are opened in reverse order

Version 4.1.0

• Added search bar to popup
  • You can disable it by option
• Added option to select behavior of popup save button and open button
• Added option not to display option page at update
• Fixed problem that color scheme was unreadable depending on OS theme
• Fixed problem that lazy load page can not be read when updating from version 3

Version 4.0.0

• Supported Google Chrome
  • Firefox and Chrome sessions are compatible
• Improved menu and notification interface on popup
• Improved stability of session restore option on startup
• Improved speed of opening session when TST option is invalid
• Remove backup limit upper limit option
  • This option was not working properly

See more release notes
https://github.com/sienori/Tab-Session-Manager/releases

I was inspired by the following great add-ons, developed as an add-on for Firefox 57 or later.
Session Manager by Michael Kraft
http://sessionmanager.mozdev.org/index.html