                     return 21
                 case .increaseIndentDepth:
                     return 22
+                case .progress:
+                    return 23
                 default:
                     return nil
                 }

            case `subscript`
            case underline
            case strikethrough
            case progress(Bool)
            case decreaseIndentDepth
            case increaseIndentDepth

            var identifier: Int? {
                switch self {

protocol SectionEditorWebViewMessagingControllerButtonMessageDelegate: class {
    func sectionEditorWebViewMessagingControllerDidReceiveButtonSelectionChangeMessage(_ sectionEditorWebViewMessagingController: SectionEditorWebViewMessagingController, button: SectionEditorWebViewMessagingController.Button)
    func sectionEditorWebViewMessagingControllerDidReceiveDisableButtonMessage(_ sectionEditorWebViewMessagingController: SectionEditorWebViewMessagingController, button: SectionEditorWebViewMessagingController.Button)
}

protocol SectionEditorWebViewMessagingControllerTextSelectionDelegate: class {
