Comment # 5 on bug 930373 from Raymond Wooninck

Are we sure that the mozilla-kde4-integration package is still being installed
?  Looking at the properties for this package, then I see 
Supplements: MozillaFirefox & kdebase4-workspace.   

As that we no longer install kdebase4-workspace, it could be that this
integration package is not installed as well. And if this package depends on
having the oxygen theme installed, then I would say that this package would
need the require for it.