On May 15th I noticed unwanted advertising in Outlook (M365 subscription) - see attached image.
I suspect it's from Microsoft (it was for Teams). That "notification" bar had an "X" at the right side to close it, which I did - and it hasn't come back since.

I should note I already subscribe to Teams.

I couldn't find anything on the web about this. I started a support incident with M365 but they're playing dumb.

I suspect MS floated it as a trial balloon to see if users would tolerate advertising in Office apps. Or maybe there's a lower-cost version which is supported by ads and they "inadvertently" turned on the ads for premium plans.

Has anyone else seen anything similar?