Hello this problem still happens to me. I wasn’t aware of this topic so I created this 20 days ago Notifications are coming again even after reading them
It suddenly started appearing after an update. For 20 days I disabled all extensions, downgraded one version and tried everything but no luck. And in our case clicking dismiss will not resolve the issue. It persists and keeps notifying user of old posts like 5 days ago 7 days ago. Even after you read them it pops up again.
Did you resolve this issue anyhow?