In Webpack 5, the [recommended way](https://webpack.js.org/guides/web-workers/) to create a web worker is

```ts
new Worker(new URL('./worker.js', import.meta.url));
```

Could we update\* the [`pdfjs-dist/webpack` entrypoint](https://github.com/mozilla/pdfjs-dist/blob/master/webpack.js) to use this syntax instead of the legacy `worker-loader`? One of the Webpack contributors told me that `worker-loader` uses "magic" and can cause issues.

\* To maintain compatibility with people still using Webpack 4, we should probably introduce a new entrypoint called `pdfjs-dist/webpack5` (or something like that) rather than changing the existing entrypoint.

Can attempt a PR if you would like.

Closely-related: https://github.com/mozilla/pdf.js/issues/15302


},
    content
  );
  return (
    licenseHeader +
    "\n" +
    GLOBALS +
    "\n" +
    MODIFICATION_WARNING +
    "\n" +
    content +
    "\n"
  );
}
gulp.task(
  "mozcentral",
  gulp.series(
    createBuildNumber,
    function scriptingMozcentral() {
      const defines = builder.merge(DEFINES, { MOZCENTRAL: true });
      return buildDefaultPreferences(defines, "mozcentral/");
    },
    function createMozcentral() {
      console.log();
      console.log("### Building mozilla-central extension");
      const defines = builder.merge(DEFINES, { MOZCENTRAL: true });
      const MOZCENTRAL_DIR = BUILD_DIR + "mozcentral/",
        MOZCENTRAL_EXTENSION_DIR = MOZCENTRAL_DIR + "browser/extensions/pdfjs/",
        MOZCENTRAL_CONTENT_DIR = MOZCENTRAL_EXTENSION_DIR + "content/",
        MOZCENTRAL_L10N_DIR =