find_more_than_es5.js

const fs = require("node:fs");
const parseEcmascriptVersion = require("ecmascript-version-detector").parse;

const browserJs = fs.readFileSync("./browser.js", "utf8");
const parsed = parseEcmascriptVersion(browserJs);
for (const expression of parsed) {
  const expressionVersion = parseInt(expression.version, 10);
  if (expressionVersion > 5) {
    console.log(expression);
  }
}