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Restore previous session

  • 2 replies
  • 1 has this problem
  • 10 views
  • Last reply by cor-el

pursig39
pursig39
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I had to update firefox. So I closed the five windows I had open then updated. When I re-opened firefox only 3 windows re-opened. How can I restore the other windows?

I had to update firefox. So I closed the five windows I had open then updated. When I re-opened firefox only 3 windows re-opened. How can I restore the other windows?

All Replies (2)

TyDraniu
TyDraniu
  • Top 10 Contributor
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The number of windows to restore is controlled by the browser.sessionstore.max_windows_undo preference in about:config.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Note that if you leave all windows open that there is no real limit because the complete session should be restored. Only when you close tabs and windows there is a limit on how many tabs (25) and windows (3) you can reopen when the session is restored on the next start.

Firefox also creates upgrade.jsonlz4-<build_id> files during an upgrade of Firefox in the sessionstore-backups folder.