ReCaptcha in an iFrame, in a container set to fixed position, disappears when scrolling

[s...@joyceinc.com]

In an iframe, in an element that's in a fixed position, ReCaptcha disappears when scrolling down, in Chrome only (latest version).

Example: http://dev.listingmanager.com/forsale/details_1299250

If you scroll down, the contact form div is supposed to follow the screen by setting the outer container to fixed positioning once the top of the window touches the top of the Div.

This works fine in Firefox, but in Chrome, the Recaptcha control disappears. I inspected every part of the element - iframe, body tag, outer div, etc. Nothing seems to be happening with CSS, so I can't figure out why it would be disappearing.

The strange part is that you can still click the invisible Recaptcha and it works as normal. However, this is obviously not acceptable because our clients' site visitors won't know it's there to click it.

If you click on the "View In Full Screen" link at the top of the page, it will open it in its own tab (not in an iframe) and this behavior doesn't happen there.