JSFiddle - React, Tailwind, and code Playground

by ult_combo

HTML

<form target="ifr" action="http://someInvalidSourceThatWillReturn404.com">
    <input type="submit">
</form>
<iframe name="ifr" id="ifr"></iframe>

JavaScript

$(function() {
    var $ifr = $('#ifr'),
    ifr = $ifr[0];

    function checkifr() {
        function errHandler() {
            alert('Error. Try again later.');
        }
        
        try {
            var d = ifr.contentWindow || ifr.contentDocument;
            if (!d) { console.log('entered if block');
                errHandler();
                return false;
            }
            
            var b = $ifr.contents().find('body');
            if (b.length && b.html()) {
                //manipulate the iframe content
            } else
                setTimeout(checkifr, 1);
        } catch(e) { console.log('entered catch block');
            errHandler();
        }
    }
    
    $('form').submit(checkifr);
});