Description: Chat notifications appear as blank tiles.
Reproduction:
- Get trust level 1
- Mention the TL1 user in chat
- Demote the user from TL1
- User gets these broken notifications:
To fix this, the chat should not appear in the notifications, and instead should not appear at all.
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I’m not sure if this is exactly the same, but does seem similar to this Bug report:
I’ll cross-link it here for extra context. 
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