set onmessage(cb) {
        onmessage = cb;
      }
@note The block below contains polyfills for Node.js globals
required for Jest to function when running JSDOM tests.
These HAVE to be require's and HAVE to be in this exact
order, since "undici" depends on the "TextEncoder" global API.

Consider migrating to a more modern test runner if
you don't want to deal with this.