• Explain the concept of how to reference fields by name in forms (of dialogs, apps, ...)
• Make sure that the "old approach" using fqcn still works
• show how to register names for custom fields.
• Provide example(s)

A few notes for the guy who will tackle:

• Every file must be registered, can be done in JCR or in YAML
• Example of a JCR based registration as they exists since .... very long: => https://demo.magnolia-cms.com/.magnolia/admincentral#app:configuration:browser;/modules/rssaggregator/fieldTypes/runRSSImportButtonField:treeview:
• Example of a YAML based definition: https://git.magnolia-cms.com/projects/MODULES/repos/dam/browse/magnolia-dam-app/src/main/resources/dam-app/fieldTypes/damUpload.yaml
• when referencing by name, the property is called fieldType, when referencing by class, the property is called class
• Fields, actually fieldTypes can be seen in the definition app as