@ Lars: Nice finding, thanks for taking your time for reporting.
** Description changed:
After update to Kubuntu 16.10 KMahjongg starts only with an empty
window, due to missing kdegames-mahjongg-data-kf5 package.
The dependency to "kdegames-mahjongg-data" was obviously removed but the
one to "kdegames-mahjongg-data-kf5" not added.
After manually installing kdegames-mahjongg-data-kf5 KMahjongg works
+ Debian does have this package as dependency 
DistroRelease: Ubuntu 16.10
Package: kmahjongg 4:16.04.3-0ubuntu1
ProcVersionSignature: Ubuntu 4.8.0-22.24-generic 4.8.0
Uname: Linux 4.8.0-22-generic i686
Date: Mon Oct 17 21:54:53 2016
InstallationDate: Installed on 2015-12-01 (321 days ago)
InstallationMedia: Kubuntu 15.10 "Wily Werewolf" - Release i386 (20151021)
UpgradeStatus: Upgraded to yakkety on 2016-10-14 (3 days ago)
+  https://packages.debian.org/sid/kmahjongg
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KMahjongg: dependency missing to kdegames-mahjongg-data-kf5
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