Remove dialog boxes from Iframe. Onbeforeunload Event Attribute.

Hi!

I have this web running with SKT White https://trtimpresiondigital.es/producto/tarjetas-de-visita-estandar-b-n/
We have embed pixlr.com/editor, an free image online editor, in that web. We are trying to set up an online print shop and we would like to offer our visitors an editor within the web. The problem is that when you try to leave the page in which pixlr.com/editor is placed, there always appear a dialog box saying “Are you sure you wan to leave this page”. This dialog appears even if you don’t implement any actions in the editor and is very annoying, so we would like to remove it.

I’ve read that this could be solved managing the “onbeforeunload Event Attribute” and I would like to know where can I find or place this attribute en SKT White files, in order to modify it and get rid of that dialog box forever.

Just let you know that in order to embed pixlr.com/editor in our web, we used Iframe plugin (https://www.ads-software.com/plugins/iframe/) including in the web this shortcode [iframe src=”https://pixlr.com/editor/” width=”100%” height=”500″]

I would appreciate any information you can provide.

Thanks indeed!!