SanjithKanagavel

function checkOnline() {
  console.log("checking online status")
  if(document.getElementsByClassName('O90ur').length > 0 && document.getElementsByClassName('O90ur')[0].textContent == "online") {
    console.log("user is online")	
    new Notification(document.getElementsByClassName('_3XrHh')[0].textContent, { body: "Online" });
  }
}

setInterval (checkOnline, 3000);

SanjithKanagavel

(
    "en_ZM",
    eu,
    "ar_TD",
    "ja_JP",
    "mer_KE",
    ast,
    ar,
    "en_KE",
    as,

SanjithKanagavel

ReactiveX (RxSwift) below are links for reference (https://github.com/ReactiveX/RxSwift) 
- For basic reference about reactive programming, start from : 
  reactivex.io,
  https://gist.github.com/staltz/868e7e9bc2a7b8c1f754,
  www.reactivemanifesto.org/,
  https://www.lightbend.com/blog/why_do_we_need_a_reactive_manifesto%3F,
  http://swiftpearls.com/RxSwift-for-dummies-1-Observables.html,
  http://swiftpearls.com/RxSwift-for-dummies-2-Operators.html
  https://www.youtube.com/watch?v=dwP1TNXE6fc 
- For rxSwift documetation :