How to remove notification popups?

[emplehod]

I uninstalled Avast Browser because it didn't work on many websites like one's that streamed video (yes, disabled ad blockers, etc.).

I am still getting popup notifications from Avast Browser but they don't open because Avast is not installed. How do I remove these notifications on my desktop?

[MiraPi]

I had a similar issue, but for me, nothing special helped. I uninstalled it after a testing week, and I kept getting those annoying notifications for 10 days after that. I didn't do anything special to get rid of it, I just turned on my computer one day and it never appeared again.