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


MOZCENTRAL_DIR + "browser/locales/en-US/pdfviewer/",
        FIREFOX_CONTENT_DIR = EXTENSION_SRC_DIR + "/firefox/content/";
      const MOZCENTRAL_WEB_FILES = [
        ...COMMON_WEB_FILES,
        "!web/images/toolbarButton-openFile.svg",
      ];
      
      rimraf.sync(MOZCENTRAL_DIR);
      return merge([
        createMainBundle(defines).pipe(
          gulp.dest(MOZCENTRAL_CONTENT_DIR + "build")
        ),
        createScriptingBundle(defines).pipe(
          gulp.dest(MOZCENTRAL_CONTENT_DIR + "build")
        ),
        createSandboxExternal(defines).pipe(
          gulp.dest(MOZCENTRAL_CONTENT_DIR + "build")
        ),
        createWorkerBundle(defines).pipe(
          gulp.dest(MOZCENTRAL_CONTENT_DIR + "build")
        ),
        createWebBundle(defines, { defaultPreferencesDir: "mozcentral/" }).pipe(
          gulp.dest(MOZCENTRAL_CONTENT_DIR + "web")
        ),
        gulp
          .src(MOZCENTRAL_WEB_FILES, { base: "web/" })
          .pipe(gulp.dest(MOZCENTRAL_CONTENT_DIR + "web")),
        createCMapBundle().pipe(
          gulp.dest(MOZCENTRAL_CONTENT_DIR + "web/cmaps")
        ),