You can't configure that in the editor for Custom Context menu ?
You can set if items should be shown for folders, files, both ?
Well yes and no.. o)
I can set whether to show the context menu entry for files or folders or both, but that does not help when clicking in the background of the file display, no file or folder selected.
Technically, clicking in the background of the file display should bring the menu items related to a folder, but it's another context, where things like "Rename", "Delete" etc. are not available. I mean they could be available, since why not rename the folder you are currently in, I actually added this functionality into another file manager I am using, but if the options don't work, it makes no sense to show them.
Maybe take a look at this screenshot:
This is Explorer's context menu on the file display background (the current folder), it also does not show "Rename", "Delete" etc., even though I technically should get all the operations being possible on a folder. I guess most people would be irritated if they could click "Delete" and the folder they are in would be removed from the disk, and the path is changed to the parent folder automatically (since the file manager does not have anything to show anymore for "this" path, which does not exist anymore).