Object deep freeze

deepFreeze.js

// https://blog.klipse.tech/javascript/2021/02/26/structural-sharing-in-javascript.html
function deepFreeze(object) {
  const propNames = Object.getOwnPropertyNames(object);
  // Freeze properties before freezing self
  for (const name of propNames) {
    const value = object[name];
    if (value && typeof value === "object") {
      deepFreeze(value);
    }
  }
  return Object.freeze(object);
}