Greetings. Forwarding up a bug report from a Fedora user. See: https://bugzilla.redhat.com/show_bug.cgi?id=505569 for full details. Basically in 4.6.0 and 4.6.1, if you try and run a command with command line arguments, and specify 'run in terminal' you get a blank terminal that sits there with nothing in it. I can duplicate this here... happy to provide more info or tests.
I guess the same fix as the panel should be applied to xfrun (r29943).
Fixed in git master.