dom ready js

JavaScript
document.addEventListener("DOMContentLoaded", function() {
  // code
});$(document).ready(function(){
  $("button").click(function(){
    $("p").slideToggle();
  });
});// without jQuery (doesn't work in older IEs)
document.addEventListener('DOMContentLoaded', function(){ 
    // your code goes here
}, false);

Source

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