Topic on Project:Support desk/Flow

I'm trying to show all categories of my wiki with <categorytree>.
Is this only possible if I have a top level category which contains all my categories?

Is it common practice to have a top level category in a wiki (up to now I don't have any)?
Help:Categories says: "It is a good idea to organize all categories into a hierarchy with a single top level category."

Thanks!

If you don't have a single top-level category, then how would you expect CategoryTree to work if you want to use it to display all your categories? I guess you could use multiple CategoryTrees on the same page.

If there is no category hierarchy at all -- your question doesn't make it clear that you have any hierarchy -- then how would you expect CategoryTree to work?

I thought there might be an option to show all categories in the root.
I had several "top level" categories - now I changed it so that I have only one top level category.
Thanks.

Good! If you don't know about it already, you might find the "hideroot" attribute handy. This is documented on Extension:CategoryTree.