Bug: Importing Oak inside a Web Worker prevents the Worker from working at all

[dhardtke]

$ deno --version
deno 1.15.3 (release, x86_64-pc-windows-msvc)
v8 9.5.172.19
typescript 4.4.2

main.ts

const worker = new Worker(
  new URL("./worker.ts", import.meta.url).href,
  {
    type: "module",
    deno: {
      namespace: true,
    },
  },
);

worker.postMessage(null);

worker.ts

import * as Oak from "https://deno.land/x/oak@v9.0.1/mod.ts";
console.assert(Boolean(Oak));

self.onmessage = () => {
  console.log("This is never printed as long as the import is present.");
};

self.onerror = (e) => {
  console.error(e);
}

Expected output:
This is never printed as long as the import is present..

Actual output:

$ deno run --unstable --no-check --allow-all main.ts

Instead of the expected output nothing is printed and it seems the worker is stuck / not properly started.

Motivation:
I have a project where Oak is imported in a deps.ts file that contains all dependencies in the project. Hence, it is also included within the worker to consume other dependencies.

[dhardtke]

This issue is still present using the latest version of Oak (1.10.0) and Deno (1.17.1)