javascript Prevent Object MutationPassed

JavaScript
let obj = {
  name:"FreeCodeCamp"
  review:"Awesome"
};
Object.freeze(obj);
obj.review = "bad"; //will be ignored. Mutation not allowed
obj.newProp = "Test"; // will be ignored. Mutation not allowed
console.log(obj); 
// { name: "FreeCodeCamp", review:"Awesome"}
Source

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