Index spaces also define generic types that are used by all doctypes.
Generic Doctype Types
The show case index space lists only one tag.
@all
Type documents automatically list all documents with the given type. Per default the search is limited to the current space (no value is specified as Space Keys). In case of index spaces typically documents of this type in any space should be listed. Therefore the special keyword @all should be used.
For the show case index space we need to limit the search to all show case spaces. Since every show case space is associated with the space category show-case the following space tag selected on those spaces:
