private static void annotateExtensions(Extensions extensions, DomElementAnnotationHolder holder) {
    final GenericAttributeValue<IdeaPlugin> xmlnsAttribute = extensions.getXmlns();
    if (DomUtil.hasXml(xmlnsAttribute)) {
      highlightDeprecated(xmlnsAttribute, DevKitBundle.message("inspections.plugin.xml.use.defaultExtensionNs"), holder, false, true);
      return;
    }

    if (!DomUtil.hasXml(extensions.getDefaultExtensionNs())) {
      holder.createProblem(
        extensions,
        ProblemHighlightType.GENERIC_ERROR_OR_WARNING,
        DevKitBundle.message("inspections.plugin.xml.specify.defaultExtensionNs.explicitly", Extensions.DEFAULT_PREFIX),
        null,
        new AddDomElementQuickFix<>(extensions.getDefaultExtensionNs()) {
          @Override
          public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
            super.applyFix(project, descriptor);
            myElement.setStringValue(Extensions.DEFAULT_PREFIX);
          }
        });
    }
  }
private static void annotateExtensions(Extensions extensions, DomElementAnnotationHolder holder)