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.
return webpackStream(webpackConfig, webpack2);
}
function getVersionJSON() {
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}
function checkChromePreferencesFile(chromePrefsPath, webPrefsPath) {
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  var chromePrefsKeys = Object.keys(chromePrefs.properties);
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    return !description || !description.startsWith("DEPRECATED.");
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  chromePrefsKeys.sort();
  var webPrefs = JSON.parse(fs.readFileSync(webPrefsPath).toString());
  var webPrefsKeys = Object.keys(webPrefs);