Every now and then I see this little red dot on the tab (which I'm assuming is shown to indicate a new incoming/unread email). I use the web version of Outlook FWIW.
However, when I switch back to the tab, I do not see any new emails. Refreshing the page also doesn't help. It happens very frequently - like 5-10 times a day during a shift.
What is Outlook trying to tell me?