docs: private void setButtonBarVisibility(Widget buttonBar, boolean visible) {
  
          String hoverStyle = I_CmsLayoutBundle.INSTANCE.form().hoverButton();
          if (visible) {
              buttonBar.addStyleName(hoverStyle);
          } else {
              buttonBar.removeStyleName(hoverStyle);
          }
          if (buttonBar instanceof CmsInlineEntityWidget) {
              ((CmsInlineEntityWidget)buttonBar).setContentHighlightingVisible(visible);
          }
          if (buttonBar.getParent() instanceof CmsInlineEntityWidget) {
              ((CmsInlineEntityWidget)buttonBar.getParent()).setContentHighlightingVisible(visible);
          }
      }