Comment # 1 on bug 1126614 from Wolfgang Bauer

Well, seems it has been fixed upstream yesterday evening:
https://cgit.kde.org/libkgapi.git/commit/?id=2a85825b3a15a6d87fd9d79a61af31927d716641

I'll add the patch to our package, though it will be in the next bugfix update
(5.10.3/KDE Applications 18.12.3) anyway.