I noticed that a couple of times when I click on an external link on a mail or a bookmarked site as icon on my mac, Firefox closes all the tabs and open that link in a new window, so I lose all the tabs and address... Sometime I have more than 30 tabs open and i't difficult to reopen all from history. What happen? Why? I can't see also the "restore last session" command into History menu. Can be fix it? Thank you.

Federico