I try to adjust automatically iframes' height acording to the contents inside Avada (WP Theme) tabs.

I found here, in stackoverflow, this code:

Before closing </body> tag:

<script type="text/javascript">
function getDocHeight(doc) {
    doc = doc || document;
    // stackoverflow.com/questions/1145850/
    var body = doc.body, html = doc.documentElement;
    var height = Math.max( body.scrollHeight, body.offsetHeight, 
        html.clientHeight, html.scrollHeight, html.offsetHeight );
    return height;
}

function setIframeHeight(id) {
    var ifrm = document.getElementById(id);
    var doc = ifrm.contentDocument? ifrm.contentDocument: 
        ifrm.contentWindow.document;
    ifrm.style.visibility = 'hidden';
    ifrm.style.height = "10px"; // reset to minimal height ...
    // IE opt. for bing/msn needs a bit added or scrollbar appears
    ifrm.style.height = getDocHeight( doc ) + 150 + "px";
    ifrm.style.visibility = 'visible';
}

document.getElementById('ifrm').onload = function() { // Adjust the Id accordingly
    setIframeHeight(this.id);
}

In each tab:

<iframe id="ifrm" src="https://TheTabUrl.com"></iframe>

It works for me but only in the first tab. I've 4 iframes in 4 different tabs in the same page. Please, any idea about the way to make it work?

Thanx for your time in advance. Greetings