(9th June 2016, 8:24)leszek Wrote: Firefox now uses the gtk3 theme engine. It might be that you have a strange one set or that Firefox in general does only support full theming on newer engine versions.
That's a minor issue. Until now I used Qtcurve for gtk2 and standard for gtk3.
The look of standard has moved, and I turned to gtk3oxygen engine in place.
I suppose that it is not the latest version of Firefox which use gtk3 theme but that was already the case before.