Missing /assets/ember.map

It’s not really a big issue, so I figured I’d just ask this here instead of creating an issue on ember-cli. My ember-cli-build.js looks like this:

let isProductionLikeBuild = !['development', 'test'].includes(env);
// ...
sourcemaps: {
  enabled: isProductionLikeBuild
'ember-cli-uglify': {
  enabled: isProductionLikeBuild

So source maps are disabled in development environment. However, I constantly get the warning in my console that it can’t find the file /assets/ember.map. It’s not really a problem, just a bit annoying that this always messes up the console a bit. I’m on the latest ember-cli & ember-source, and not quite sure why that is happening. Does anybody have an idea how to get rid of this warning?

Source map error: Error: request failed with status 404
Resource URL: http://localhost:4200/assets/vendor.js
Source Map URL: ember.map