JSFiddle - React, Tailwind, and code Playground

HTML

<iframe></iframe>
<iframe src=""></iframe>

JavaScript

logBody('src: ' + $('iframe')[0].src);
logBody('src: ' + $('iframe').attr('src'));

logBody('src: ' + $('iframe')[1].src);
logBody('src: ' + $('iframe:eq(1)').attr('src'));

logBody($('iframe[src=""]').length);


function logBody($r){
   $('body').append('<p>' + $r + '</p>');  
}