On https://github.com/mozilla/pdf.js/wiki/Required-Browser-Features we mention required browser features for PDF.js, but I have the feeling that not all of them are necessary nowadays since we moved to using more modern features over the years. Moreover, as indicated in https://github.com/mozilla/pdf.js/issues/11950#issuecomment-637149085, some features may be missing such as range requests or `async/await`.

In short, we should verify which are still necessary and update the wiki page and the automated feature detection if possible.
.pipe(replace(/\bPDFJSSCRIPT_COMMIT\b/g, commit))
        .pipe(gulp.dest(MOZCENTRAL_EXTENSION_DIR)),
      gulp.src("LICENSE").pipe(gulp.dest(MOZCENTRAL_EXTENSION_DIR)),
      gulp
        .src(FIREFOX_CONTENT_DIR + "PdfJsDefaultPreferences.jsm")
        .pipe(transform("utf8", preprocessDefaultPreferences))
        .pipe(gulp.dest(MOZCENTRAL_CONTENT_DIR)),
    ]);
  })
);
gulp.task("mozcentral", gulp.series("mozcentral-pre"));
gulp.task(
  "chromium-pre",
  gulp.series(
    "buildnumber",
    "default_preferences",
    "locale",
    function scripting() {
      var defines = builder.merge(DEFINES, { CHROME: true, SKIP_BABEL: false });
      return createTemporaryScriptingBundle(defines);
    },
    function () {
      console.log();
      console.log("### Building Chromium extension");
      var defines = builder.merge(DEFINES, { CHROME: true, SKIP_BABEL: false });
      var CHROME_BUILD_DIR = BUILD_DIR + "/chromium/",
        CHROME_BUILD_CONTENT_DIR = CHROME_BUILD_DIR + "/content/";
      
      rimraf.sync(CHROME_BUILD_DIR);
      var version = getVersionJSON().version;