I'm having reasonable success doing what I want to do with the FF Add-on for Identity Safe (FF 48.0.2) but have noticed one issue that is a bit of a pain. If I do not yet have my vault open, have multiple FF tabs open and in the active tab I encounter a logon request, the Identity Safe pops up with a request to open my vault. If I do that and the vault opens, FF (or the add-on, don't know which) proceeds to position me on the right-most tab, not necessarily the one where I was in the process of performing the login. If I return to the tab where I was logging in I am properly logged in. Not sure if the add-on could take on the responsibility of returning me to the tab I was using. I gather that the add-on needs its own tab to perform its open but when that tab closes the addon apparently loses track of what tab it originated from and you are not sent back there instead of the tab that immediately preceded the temporary Norton tab.