nuxeo filter does not work in custom form

1. Install Nuxeo 9.3
2. In Modeler, create a custom document type
3. In the Designer create custom forms
4. In the forms add the following:

       User:[[user]]<br>
       currentUser:[[currentUser]]<br>
       <nuxeo-filter user="[[user]]" expression="user.isAdministrator">
         this user is admin
       </nuxeo-filter><br>
       <nuxeo-filter user="[[user]]" expression="!user.isAdministrator">
         this currentUser is NOT admin
       </nuxeo-filter>
       <nuxeo-filter user="[[currentUser]]" expression="currentUser.isAdministrator">
         this currentUser is admin
       </nuxeo-filter><br>
       <nuxeo-filter user="[[currentUser]]" expression="!user.isAdministrator">
         this currentUser is NOT admin
       </nuxeo-filter>
   

5. Log in as Administrator
6. Sync the project with the server
7. Click the + button to create a document
8. Observe this does not display any value for user or currentUser (see createForm.png)
9. Observe all the messages are displayed: this user is admin, this user is NOT admin, this currentUser is admin, this currentUser is NOT admin (see createForm.png)

Expected behavior : user or currentUser should be valued and only the nuxeo-filter bloc for the admin should be displayed.