@Override
  public boolean handleExternal(PsiElement element, PsiElement originalElement) {
    for (DocumentationProvider provider : getAllProviders()) {
      if (provider instanceof ExternalDocumentationHandler &&
          ((ExternalDocumentationHandler)provider).handleExternal(element, originalElement)) {
        LOG.debug("handleExternal: ", provider);
        return true;
      }
    }

    return false;
  }
@Override
  public boolean handleExternal(PsiElement element, PsiElement originalElement)