This seems like a pretty big bug:
Using Windows 10 Home on a ThinkPad X1 Carbon (7th gen). This is my main work machine, but my wife uses it in the evenings under her own Windows account. I don’t log out of my account, I just close the lid when I’m done, which locks the laptop. When my wife opens the lid, she just uses the fingerprint scanner and logs into her account.
While using her account, she gets the audio notification for new emails from eM Client, which is running in my account. There is nothing in the Windows notification centre. Checking Task Manager, there are no eM Client-related processes listed. eM Client is not installed for her Windows account and she does not run it.
She can’t access my email (or my Windows account), but from a security and privacy standpoint, she really shouldn’t know that I have emails coming in. In this instance it doesn’t matter, because it’s just us at home, but in a secure work environment, this seems very problematic.
I assume by not actually logging out, my Windows account is just hibernating behind the other account currently being used (and visa versa). But this “bleed” of notifications is very strange and very concerning.