code: public static boolean linkFrom(String basePath) {
          if (Objects.equals(basePath, LINK_FROM.get())) return false;
          if (basePath == null) LINK_FROM.remove();
          else LINK_FROM.set(basePath);
          return true;
      }
docs: Sets the base path where relative links should be rendered from.
  <p>
  This setting is configured on a per-thread basis.
  
  @param basePath The base path to define relative links from.
  @return whether the base path was modified or not