How to decode this code?

Question

JavaScript

There is this code:

<script>
        window.onload = function() {
    var B = document.getElementById('meme');
    var i = 0;
    //
  
    var perfecto = function(s) {
      var e={},i,b=0,c,x,l=0,a,r='',w=String.fromCharCode,L=s.length;
      var A="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
      for(i=0;i<64;i++){e[A.charAt(i)]=i;}
      for(x=0;x<L;x++){
        c=e[s.charAt(x)];b=(b<<6)+c;l+=6;
        while(l>=8){((a=(b>>>(l-=8))&0xff)||(x<(L-2)))&&(r+=w(a));}
      }
      return r;
    };
        function calctime(){
        B.innerHTML = perfecto(perfecto("UW05dmMzUmxSQ0JUYVd4MlpWST0="));
        };
        init();
        function init() {
        setInterval(calctime, 10);				
        };
            }
    </script>

As soon as I did not try to decode it and everything is in vain, can anyone help? I will be very grateful!

Answer 1

chrome + jsfiddle.net + F12 +
add in the first line. debugger;

Answer 2

Decode - read or break?)