JSFiddle - React, Tailwind, and code Playground

JavaScript

function checkConnection() {
    var connected = true;
    var img = document.createElement('img');
    img.src = "https://p5-zbjpil5uzqzqg-b5icu4xm7kglqch5-458861-i2-v6exp3-ds.metric.gstatic.com/v6exp3/6.gif";
    img.onerror = function () {
        connected = false;
    };
    return connected;
}
setInterval(function () {
    var isConnected = checkConnection(); // checkConnection() comes from above code
    if (isConnected) {
        console.log('internet');
    } else {
       console.log('no internet');
    }
}, 3000);