code: @Override
      public CmsFile writeFile(CmsObject cms, CmsSecurityManager securityManager, CmsFile resource) throws CmsException {
  
          String savingStr = (String)cms.getRequestContext().getAttribute(CmsContentService.ATTR_EDITOR_SAVING);
          CmsFile file = super.writeFile(cms, securityManager, resource);
          // Formatter configuration cache updates are asynchronous, but to be able to reload a container page
          // element in the page editor directly after editing it and having it reflect the changes made by the user
          // requires that we wait on a wait handle for the formatter cache.
  
          if (Boolean.valueOf(savingStr).booleanValue()) {
              CmsWaitHandle waitHandle = OpenCms.getADEManager().addFormatterCacheWaitHandle(false);
              waitHandle.enter(10000);
          }
          return file;
      }
docs: @see org.opencms.file.types.CmsResourceTypeXmlContent#writeFile(org.opencms.file.CmsObject, org.opencms.db.CmsSecurityManager, org.opencms.file.CmsFile)
  
  After writing the file, this method waits until the formatter configuration is update the next time.