When trying to decorate workflow:publish it is not working and the following error is thrown:

Caused by: java.lang.ClassCastException: info.magnolia.ui.dialog.formdialog.FormDialogPresenterImpl cannot be cast to info.magnolia.module.workflow.action.WorkflowFormDialogPresenter
	at info.magnolia.module.workflow.action.OpenPublicationDialogAction.execute(OpenPublicationDialogAction.java:57)
	at info.magnolia.ui.api.action.AbstractActionExecutor.execute(AbstractActionExecutor.java:62)
	... 124 more

Exception is thrown because the expected presenterClass is not returned by info.magnolia.config.registry.decoration.CachingDefinitionDecorator.decorate(DefinitionProvider<T>) (this method is returning decorationResult, but decorationResult didn´t have the good definition).

Definition app display the expected configuration, the decoration is correctly done.

It is easily reproducible. Create file /<my-light-module>/decorations/workflow/dialogs/publish.yaml with this content:

form:
  tabs:
    comment:
      fields:
        comment:
          required: true

When you try to publish a page from pages, it cannot be done because an error comes up and the dialog is not displayed.