I had the same issue, I went to Session settings and disabled session saving. I can't remember the exact names of them but I think that you'll find it.
That did it! Thank you!
My solution: Desktop Session - System Settings > Session Restore > Start with an empty session
I could probably alternately add the Discover app to the Ignored applications list, but I prefer a fresh session on start.
Glad I could help! I only found out how to solve it today. Funny that I could use the knowledge immediately too.
This has only started for me after the last 6.1 update.
The only app I have to autoluanch is Betterbird.
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