Group Chat maildelivery marked as failed everytime, person can't leave group

[LauerViolence]

In our Group-Chat one of the group-members uninstalled signal and doesn't have google play anymore. The corresponding number is still part of the group, but she can't get the messages anymore, because she doesn't have signal. We can't remove the number from the group and she can't leave, so every message gets marked as not delivered.

EDIT------------------------------------------------
Step by step:
-Make a group-conversation including phone-nr. A, B and C
-phone C uninstalls Signal but is still in the group
-phone a sends a message
-phone B receives said message, phone C (of course) doesn't
-phone A gets "message could not be sent"

Result: Every message gets marked as undelivered because of phone C not having Signal anymore
Expected/Ideal Result: phone C automatically gets kicked out of the group when Signal is not installed anymore, every message gets delivered.

Device Info:
Happens to all 10 different phones in our group, mine would be:
ZUK Z1
Cyanogen OS 12.1-YOG4PAS7DF
Android version: 5.1.1
Signal Version: 4.6.1

Debug Log:
https://gist.github.com/ff13303a26e8d8a8bbe03edba8b04531

[nrizzio]

This is (probably) a duplicate of #828.

[haffenloher]

every message gets marked as not delivered.

I think this shouldn't happen, but it's hard to diagnose without more info. Please fill out the issue template and include a debug log captured right after a failed send.

[trmendes]

Number #828 is closed. I jusy wrote a message there regarding to something related to user management in a group chat and I'm wondering if someone is gonna read it or not since it is a closed issue.

[automated-signal]

GitHub Issue Cleanup:
See #7598 for more information.