The HTML element is set to fixed height in WiX code now. This is a problem when the embedded HTML-code contains data thats varies in height depending on how the user interacts with the content presented by the HTML-code.
This problem makes bad usability. Senario: A user is filling out a form with 3 steps. Step 1 is only 400 pxl in height, step 2 is 3000 pxl in height and step 3 is in 1000 pxl height. All steps has a "next" button in bottom of the page. When user goes from step 2 to 3, the page continues to stay on the same spot on the screen, making the view of the screen blank, since the content is only 1000 pxl in height. The user needs to scroll up to see the content.
This issue is related to the fixed heigth of the iframe or div in WIX code. We have tested that together with a booking engine called Sirvoy.
This issue is also reflecting the responsivness of the embedded HTML-code. It gets poorer through your HTML-element.
The thing is that Wordpress.com solves this perfectly, the embedded HTML-code´s content shows up with a dynamic height when going through the steps, and it scrolls up to top of embedded HTML-code.
I have tested the external HTML with W3C Try Editor, so there is no problem with that.
I have been in contact with WiX support, that said that this is the behaviour of the HTML-element, so it needs to be developed by WiX in order to be dynamic in height.
I see that this issue is already diskussed in the Forum for almost a year a go, so it´s an "old" problem and highlighted by others too. https://www.wix.com/corvid/forum/community-discussion/html-iframe-with-dynamic-height
I hope you will put a high prioritise on this feature in you backlog. When Wordpress.com can, so can WIX, right?
If you want some examples, I gladly share some URL´s with you.