I have 1 firefox account, and two different outlook mail accounts. How can I keep both email accounts open simultaneously? First I open a firefox private window, and then i open a MS Outlook email instance, disabling all optional cookies. Then I open a second private Firefox instance, and when I open the second MS Outlook instance (cookies disabled like above), the MS account auto-opens the account I already opened. If I sign out of the second instance, the first instance also closes. I sign in to the second instance with the other MS Outlook account, the first MS account (in the previously opened private window) opens to the second MS outlook account. I want to have both MS outlook accounts open simultaneously. I was able to do this in Windows 10. What changed, and how do I get the Windows 10 (preferred) behavior back? Thanks