Allows Observable notebooks to statically import ES modules as Runtime modules.
See https://observablehq.com/d/1ff60814f0002dd5 for details and examples.
https://mootari-observable_esm.web.val.run
https://esm.town/v/mootari/observable_esm
<script type="module" src="https://esm.town/v/mootari/observable_esm" />