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.
gulp.task(
  "bottest",
  gulp.series("testing-pre", "generic", "components", function () {
    return streamqueue(
      { objectMode: true },
      createTestSource("unit", true),
      createTestSource("font", true),
      createTestSource("browser (no reftest)", true),
      createTestSource("integration")
    );
  })
);
gulp.task(
  "browsertest",
  gulp.series("testing-pre", "generic", "components", function () {
    return createTestSource("browser");
  })
);
gulp.task(
  "unittest",
  gulp.series("testing-pre", "generic", function () {
    return createTestSource("unit");
  })
);
gulp.task(
  "integrationtest",
  gulp.series("testing-pre", "generic", function () {
    return createTestSource("integration");
  })
);