I experienced this issue as well. I wanted to add that installing the package gtk2-engines-qtcurve did not resolve the issue (in fact it was already installed when the issue started).
I had to go to the Clearlooks theme in order to fix this.
I experienced this issue as well. I wanted to add that installing the package gtk2-engines- qtcurve did not resolve the issue (in fact it was already installed when the issue started).
I had to go to the Clearlooks theme in order to fix this.