Could increase the number of "restore previous session" options. Because if a user have a closed session, open Firefox, open a tab, and forget to restore the previous session, the previous session is gone, because it will be the session for that new tab. If the "restore previous session" option worked twice, it would be better, because user would only need to use the function twice and the session you really want to recover would be recovered. The main competitor in the market allows the user to recover multiple times and Firefox would gain points if it also allowed using the session recovery function multiple times