JSFiddle - React, Tailwind, and code Playground

JavaScript

// Get the start of code execution
var start = new Date();

// Mimics a long running call for a number of milliseconds 
function waitMilliseconds(milliseconds) {
  var start = +(new Date());
  while(start + milliseconds > +(new Date())) {}
}

var first = true;
setInterval(function() {
    var current = new Date();
    console.log('setInterval executing: ' + (current - start));
    
    // Make the first execution take 1.5 seconds
    if (first) {
        waitMilliseconds(1500);
        first = false;
    }
}, 1000);