Loading spinner for iFrame Fancybox

[Patta]

Is your feature request related to a problem? Please describe.

It would be great if there 's a option to add the loading spinner to iFrame Fancybox as well (for better UX). This seems to be a missing feature/option in version 6.

Describe the solution you'd like

JS Bin Example: https://jsbin.com/duyayaguze/edit?html,console

Describe alternatives you've considered

Added custom spinner to fancybox container with initLayout and hide spinner with Carousel.render event if iframe is loaded.

Additional context

Upgraded from v4 to v6. In v4 the loading spinner was added by default for iframes.