KDE 4.12.2 Released Along With Plasma WS 4.11.6

[molecule-eye]

I have exactly the same problem and it's really ugly!
It looks like the bug is related to gtk or whatever "old"-style icons. In my case I've closed dropbox and skype, have resized the tray and it helped. But I need skype and dropbox

Yeah, non-KDE apps that show up in the systray are a real pain. For instance, I've made my panel quite thin so that the KDE systray icons match dropbox and skype in size, but the tray icon for HP's printer manager is huge now. Good thing it can be hidden, but it's not always convenient to do so. I wish there was some better, CROSS-DE, way of dealing with tray icons so that it worked everywhere. Like if they all used svg so they scaled unproblematically.