message: fixup! [cli] Only inject custom-elements-es5-adapter.js when compiling to ES5
diff: @@ -55,7 +55,7 @@ export async function build(
  const compiledToES5 = (options.js === undefined) ?
  false :
  - options.js.compile === true || options.js.compile === false;
  + options.js.compile === true || options.js.compile === 'es5';
  if (compiledToES5) {
  buildStream =
  buildStream.pipe(polymerProject.addCustomElementsEs5Adapter());
  