Parameter Types (html_displayer): date, userreference - some questions

It is possible to use a (predefined) parameter type defining a macro parameter.
When entering the macro call in WYSIWYG mode in the editor some special pickers are used.

  • java.lang.Boolean generates a fine checkbox to enter a boolean value
  • org,wiki.model.reference.DocumentReference gives a filtering picker for documents
  • org.wiki.model.reference.AttachmentReference gives a filtering picker for attachments
  • java.awt.Color gives a color picker

that is fine, but

(1) java.util.Date generates an error message if the date picker is activated:

         ...  DateConverter does not support defaiöt String to 'Date' conversion

The date picked is delivered to the source.

Must I use a different class?

(2) There exists a “userreference” within webbapps/templates/html_displayer. but I missed any corresponding class (something like “org.wiki.model.reference.userreference”)

Does a suitable class exist?

I am currently using version 11.10.10.

An additional comment:

It would be a nice addition if in the future there were a standardised way to generate whether parameters of type checkbox or radio. I know that I could achieve this in individual cases by means of a Java program, but that is quite exhausting in individual cases.

Thanks
Norbert