Comment 146 for bug 1589401

I have only seen this when resuming from suspend.

For the upstream developers, we need to add to /etc/NetworkManager/NetworkManager.conf:
[logging]
level=TRACE

Then restart, and when the issue is observed, capture the networkmanager logs with:
journalctl -u NetworkManager -b

and put into:
https://bugzilla.gnome.org/show_bug.cgi?id=767317