">

    <!-- resolves only if srcset contains the concrete value via filter -->
    <img srcset="assets/img/fig.c6809878.png, assets/img/fig2.c6809878.png, assets/img/fig3.c6809878.png">

    <!-- custom tag with custom attributes used in filter -->
    <custom-img
      data-src-one="@images/fig.png"
      data-src-two="assets/img/fig2.c6809878.png"
      data-resolve-attr="data-src-two"
      src="@images/fig3.png"
      alt="custom image"
    />
  </body>
</html>