Programmatically move or hide Episerver Forms Actors in Edit View

The built-in "Send Email"-Actor in Episerver Forms lives on the Settings tab in Edit View by default.

My customer wanted to move everything to do with sending a form to a separate tab, including the actors, and hide the webhook actor. 

The only solution I found online was to do it from the Admin interface, but I wanted to do this programmatically to avoid having to change the property setting from Admin after deploy to our various environments.

I tried using an Editor Descriptor but could not quite get it to work, so I asked the Episerver Developer Support and got the following solution from them that worked perfectly:

[EditorDescriptorRegistration(
        TargetType = typeof(IEnumerable<EmailTemplateActorModel>), 
        UIHint = "EmailTemplateActorEditor",
        EditorDescriptorBehavior = EditorDescriptorBehavior.OverrideDefault)]
    public class EmailTemplateActorEditorDescriptor : CollectionEditorDescriptor<EmailTemplateActorModel>
    {
        public EmailTemplateActorEditorDescriptor()
        {
            ClientEditingClass = "epi-forms/contentediting/editors/EmailTemplateActorEditor";
        }
        public override void ModifyMetadata(ExtendedMetadata metadata, IEnumerable<Attribute> attributes)
        {
            GridDefinition.GridSettings["richTextColumns"] = new[] { "body" };

            base.ModifyMetadata(metadata, attributes);

            metadata.GroupName = GlobalSettings.GroupNames.SendTab;
            metadata.Order = 50;

            //...if you want to hide the actor, set metadata.ShowForEdit = false;
        }
    }

(The Send Email actor contains a rich text editor, which is why the GridDefinition settings are needed when overriding the Metadata function above.)

I hope this can help others that would like to do the same thing.