index.js

const instance = {};

console.log(instance.__proto__ === Object.prototype); // true, 浏览器才需要部署
console.log(instance.constructor.prototype === Object.prototype); // true, 改变 prototype 时没有同步修改 constructor 时会异常
console.log(Object.getPrototypeOf(instance) === Object.prototype); // true, 靠谱