What's the right way to select Thunar as the default app for folders in Firefox?

[alowe]

I tried the following at the Terminal:

Code:

xdg-mime default /usr/share/application/Thunar-folder-handler.desktop inode/directory

But when I select the downloads icon in Firefox, then select a folder , nothing happens.

The folder exists and xdg-mime query confirms the mime type is set. Although Firefox lists all Applications used to open files by type in its Preferences, this does not include inode/directory. That was the first place I checked.