Compatibility problems with latest GTK+ applications

[David Edmundson]

It seems changing the GTK style to Oxygen fixes a lot of the visual problems.
Kwin is doing the decoration and the borders. I don't get the shadows
with compositing on/off.

http://imgur.com/5aiDUFq

Martin could you try setting this and see which bugs remain?
It seems all things are fixed, besides a slightly silly double title.

David