The message panel has a colored background that jars with the red close icon. Reproducible: Always
screenshot please
The URL shows all three types of message panels.
Likely fixed, see https://git.reviewboard.kde.org/r/126523/
I'm not sure if it's actually fixed, both window-close and dialog-close do not really work on the colored backgrounds of KMessageWidget. I'm just not sure if that's something that should be fixed in the icon or in KMessageWidget (by setting a background for the button, for example)
Reopened and moved to kwidgetsaddons, fix in https://phabricator.kde.org/D3418
Git commit 497c463a4a430f8bef726bc415011d231bf9cf46 by Elvis Angelaccio. Committed on 30/12/2016 at 11:29. Pushed by elvisangelaccio into branch 'master'. KMessageWidget: use darker red color when type is Error Otherwise the close button is barely visible. There isn't an easy way to change to color of the close button icon, so we use a slightly darker background color instead. FIXED-IN: 5.30 Differential Revision: D3418 M +2 -0 src/kmessagewidget.cpp https://commits.kde.org/kwidgetsaddons/497c463a4a430f8bef726bc415011d231bf9cf46