Getting messages after leaving a group

User story: After leaving a group the person might still be able to read messages in a thread they are part of when they get the notification. Thread is not opened (see screenshot), but part of the content is visible in the notification

No messages, unless it’s a direct private message, should reach the person who left the group.

Noticed before: Receiving chat messages after leaving a group

Complexity: ?

Outcomes (or what needs to be done to move forward): investigate the causes