About 80% of the time, Discover successfully finds updates but once they're selected and the install button is pressed the program hangs instead of popping up a password prompt. Discover then can't be closed as it states that a process needs to complete and the Discover process must be killed in order to exit it. The other 20% of the time, Discover displays the password prompt and everything works fine. Could some kind of error checking be added to check whether the password prompt was successfully generated and either launch it again or generate an error condition so Discover can be exited without needing to kill its process?
The prompt comes from PackageKit, assigning to Neon.
Seeing same problem
It appears that this is resolved on the following https://bugs.kde.org/show_bug.cgi?id=397759 *** This bug has been marked as a duplicate of bug 397759 ***