rget), window.Function.prototype);
      assert_equals(Object.getPrototypeOf(o), window.HTMLElement.prototype,
        "Must use the HTMLElement from the realm of NewTarget");
      assert_not_equals(Object.getPrototypeOf(o), w.HTMLElement.prototype,
        "Must not use the HTMLElement from the realm of the active function object (w.HTMLElement)");

      return o;
    }

    // Create the proxy in the subframe, which should not affect what our
    // prototype ends up as.
    const ElementWithDynamicProt