Don't flag space as unread if I sent the last message

[Charlerlin]

Current beheviour is to flag space as unread if there are "new messages" when I leave the space. Nice to think about the fact that I might leave the space without fully reading all received messages. However, when I sent the last message, this is not necessary and may lead to misinterpretation.

Expected behaviour: don't flag space as unread if the latest message was written by me ;)