Teams pop-up notifications can be controlled through the Settings screen:
- Click on your initials/photo at the top right, then Settings:
- Click on Notifications:
- For each of the entries (Chat/Meetings/People/Other) you can click Edit and pick which notifications you want - where it is set to "Banner" it will pop up, "Feed" it shouldn't pop up.
- Finally you can click on Custom and there are some more settings which can be turned off.
- As a final step you can turn off notifications completely within Windows by clicking the Start menu then begin typing in "Notifications", then click on Notifications and actions settings when it appears:
- You can then turn off notifications altogether here: