Thread:Project:Support desk/Removing something from a sidebar/reply (9)

I have another question: You know the Vector skin. And the Vector extension. This extension makes the the "categories" in the sidebar collapsible and expandable ([this] instead of this). The problem is that I cannot install a Vector extension on my wiki because I do not use the Vector skin. But how can I make the categories of my wiki's sidebar collapsible and expandable?

Is it as easy as adding a piece of programming code to the Common.css?