You would definitly need http/2 to use this, I've tried using imports in vanilla...

plopz on Jan 9, 2020 | parent | context | favorite | on: Snowpack: Build a web application without a bundle...

You would definitly need http/2 to use this, I've tried using imports in vanillajs with supported browsers its sloooooooow. I do wonder whether you could leverage server push for this and whether that would help.