Has anyone seen a message like the following, which I started getting when I upgraded from F30 to F31. It comes from dolphin when attempting to view some (but not all) files in my Trash folder and also from ksensors . The problem has been reported on some other forums, e.g. 
https://forums.fedoraforum.org/showthread.php?322688-ICEauthority-problem-after-30-gt-31-upgrade&p=1828892#post1828892
but there doesn't seem to be any clear analysis or a solution.  

Any ideas? If I file a bug, where should it go?

$ ksensors ICE Connection rejected!

DCOPClient::attachInternal. Attach failed Authentication Rejected, reason : None of the authentication protocols specified are supported and host-based authentication failed
ICE Connection rejected!

Thanks - jon