Note that you can right-click a tab, goto "save" and choose "all tabs to a speed dial folder" to back up your tabs. Then, if they disappear, you can right-click that folder and choose to open all of its bookmarks in tabs all at once to get your tabs back (from the time you created the folder).
You can also try Session Buddy or a similar extension to save your open tabs so you can get them back in a crisis.