Web Worker Initialisation Crash without Error

When I create a faulty web worker, it immediately terminates. However, the browser console does not show any error messages, which is strange.

This seems to be reproducible both in Firefox and Chrome.

let code = `
import { crash } from "./nowhere.js"; 
console.log("hi"); // Never gets executed
`;

let alternateCode = `
console.log("hi");
throw new Error("normal errors do show up in the browser console");
`;

let blob = new Blob([code]);

let blobURL = window.URL.createObjectURL(blob);
let worker = new Worker(blobURL);
worker.onmessage = (data) => {
    console.log(data);
};
worker.postMessage("start");

// And check out the browser console