I messed around with tab groups and somehow closed it all. Now all my tabs are gone!

Question

I clicked on the "tab groups" button and not knowing what it was or what it does, I seemed to have closed all my tabs (30+). Now they are all gone, except for 10 which i saved from 'recently closed tabs'. Can anyone help! I had important tabs open and do not remember the links or how to get them again!

Answer 1

(for future usage) You can specify the number of Tabs and Windows you can undo in a session. Here's how:-
Type '''about:config''' in the Location (address) bar and press the "Enter" key. When you see a warning, click '''I'll be careful, I promise!''' button.
* Preferences that have been modified are shown as '''bold (user set)'''.
* Preferences can be '''Reset to the default''' or changed via the right-click context menu.
-> In the '''Filter bar''', type '''browser.sessionstore.max_tabs_undo'''
* right-click the preference '''browser.sessionstore.max_tabs_undo''' -> click '''Modify''' -> type the number -> click OK
-> In the '''Filter bar''', type '''browser.sessionstore.max_windows_undo'''
* right-click the preference '''browser.sessionstore.max_windows_undo''' -> click '''Modify''' -> type the number -> click OK
-> Close the '''about:config''' tab and Restart Firefox.
Check and tell if its working.