can I put markup inside an iframe tag in a rich text field?

Question

I need to support embedded tweets in Facebook Instant Articles. Oob the way to do that is to wrap Twitter's embed code blockquote.twitter-tweet in figure.op-interactive iframe (here's a link to Facebook's documentation, for reference) —

<figure class="op-interactive">
  <iframe>
    <blockquote class="twitter-tweet"...</blockquote>
  </iframe>
</figure>

I planned to add those wrapping elements via the "source" view of the rich text field, but when I save EE escapes the < and > inside the iframe as < and > —

<figure class="op-interactive">
  <iframe>
    &lt;blockquote class="twitter-tweet"...&lt;/blockquote&gt;
  </iframe>
</figure>

Is there a way to include markup inside an iframe in the rich text editor?

Or does anyone have a favorite workaround? Or a plugin that could be added to this large existing site without adding tooo much migration overhead and without significantly changing the client's content entry experience?

This site is on EE 2.9 if that makes a difference.

Answer 1

I solved something simulair with https://devot-ee.com/add-ons/low-replace, an addon from LOW. I wanted special markup for any <a href in the RTF field. It works like a charm!

In my case like this:

{exp:low_replace find="<a "
                 replace="<a class='lightview'
                            data-lightview-type='iframe'"
}
  {My_RTFText_Field}
{/exp:low_replace}

Answer 2

You shouldn't use rich text editor for this as it will convert the HTML tags for sure. Try using TextArea field instead.