- Create an Action which extends from a class other than CancelDialogAction or SaveDialogAction (both deprecated)
- Add such action to a dialog on the PostCreate method (as stated on the documentation)
The action appears at the bottom of the dialog.
If the action doesn't extend from SaveDialogAction or CancelDialogAction, no action appears.
An option would be to expose ACTION_CONVERTERS same way as FIELD_DEFINITION_CONVERTERS.