Detect when your site is visible to users

document.onvisibilitychange = function () {
          document.visibilityState === "visible"
             ? (document.title = "👋 Hello")
             : (document.title = "😟 Bye!");
       };

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Promise + gì

promise + gì

Rest Operator for Objects

Now we can use rest on the properties of an Object. It allows us to explicitly extract certain named variables, and assign any uncalled variables into a catchall Object.

JavaScript: async/await with forEach

JavaScript: async/await with forEach()

group by property javascript use reduce

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