Allows Firefox to start off where you were when you closed it, keeping all windows and tabs intact.
Compatibility 
Works with: Firefox 3.6+
Background
By default when closing Firefox, current tabs and windows are not persevered.
The Tweak
Firefox can be configured to remember the tabs and windows open from the previous session and reopen these as they were upon start of the session.
- From Tools Menu select Options…’
- From the Main tab in the Startup section, When Firefox starts: select from the drop-down menu Show my windows and tabs from last time
- Click OK
Notes
Updated: November 15, 2025
