   FroalaEditor.RegisterCommand('myButton', {
      title: 'Show Popup',
      icon: 'buttonIcon',
      undo: false,
      focus: false,
      popup: true,
      // Buttons which are included in the editor toolbar should have the plugin property set.
      plugin: 'customPlugin',
      callback: function () {
        if (!this.popups.isVisible('customPlugin.popup')) {
          this.customPlugin.showPopup();
        }
        else {
          if (this.$el.find('.fr-marker')) {
            this.events.disab