code: public static String getFileExplorerLink(CmsObject cms, String siteRoot) {
  
          return CmsVaadinUtils.getWorkplaceLink()
              + "#!"
              + CmsFileExplorerConfiguration.APP_ID
              + "/"
              + cms.getRequestContext().getCurrentProject().getUuid()
              + "!!"
              + siteRoot
              + "!!";
      }
docs: Returns the file explorer link prefix. Append resource site path for complete link.<p>
  
  @param cms the cms context
  @param siteRoot the site root
  
  @return the file explorer link prefix