Bug 406125

SUMMARY

I've had this problem at least since kf5 5.38, plasma-workplace 5.10.5, Fedora 25.

Now on kf5 5.54, plasma-workspace 5.13, Fedora 28.

I disable Klipper.

The clipboard will just stop working, or work erratically, in my main KDE apps: KMail, KAlarm, Konqueror, Konsole.

The clipboard doesn't seem to get populated by a KDE Ctrl-C/X, or highlighting. Ctrl-V or middle-click pastes whatever non-KDE app did a Ctrl-C/X or highlight.

Seems like KDE disconnects from its own and the X clipboards.

I had to use Chrome to file this bug report because Konqueror does NO copy/paste.

STEPS TO REPRODUCE
1. In a KDE app, Ctrl-C/X or highlight
2. In any other app, KDE or not, Ctrl-V or middle-click

OBSERVED RESULT

Whatever a non-KDE app left in the KDE/X clipboards is pasted.


EXPECTED RESULT

Whatever was Ctrl-X/V or highlighted into the clipboard should be Ctrl-V or middle-click pasted.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 5.13.5
(available in About System)
KDE Plasma Version: 5.13
KDE Frameworks Version: 5.54
Qt Version: 5.11.3

ADDITIONAL INFORMATION

This behaviour seems to coincide with windows opening in the background, e.g., when I opened KInfoCenter from the K Menu to check versions it opened minimized to the Task Bar.