Why do SSL embed codes load non-SSL resources?

The embed code specifies an SSL URL but non-SSL resources are requested.

E.g.

<iframe id="iframe_container" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen="" width="550" height="400" src="https://prezi.com/embed/cdlf6d7vzikj/?bgcolor=ffffff&amp;lock_to_path=0&amp;autoplay=0&amp;autohide_ctrls=0&amp;PARENT_REQUEST_ID=9d85ffae285d1825#"></iframe>

In browser console:

Mixed Content: The page at ‘https://prezi.com/embed/cdlf6d7vzikj/?bgcolor=ffffff&lock_to_path=0&autoplay=0&autohide_…’ was loaded over HTTPS, but requested an insecure plugin data 'http://prezi.com/api/embed/?id=cdlf6d7vzikj’. This content should also be served over HTTPS.prezi.com/:1 Mixed Content: The page at ‘https://prezi.com/embed/cdlf6d7vzikj/?bgcolor=ffffff&lock_to_path=0&autoplay=0&autohide_…’ was loaded over HTTPS, but requested an insecure plugin data 'http://cdn-a.prezi.com/crossdomain.xml’. This content should also be served over HTTPS.
prezi.com/:1 Mixed Content: The page at ‘https://prezi.com/embed/cdlf6d7vzikj/?bgcolor=ffffff&lock_to_path=0&autoplay=0&autohide_…’ was loaded over HTTPS, but requested an insecure plugin data 'http://cdn-a.prezi.com/fonts/TriplexSansOT-Bold.swf’. This content should also be served over HTTPS.

Hi Mike, 

Thanks for your patience in this matter.

I would like to give you a feedback and thank you for the details.
This is very helpful in order to improve our site. I spoke to one of our developers and he confirmed that the embed player is - not fully switched to HTTPS yet. I reported the issue and our developers will do their best to resolve it as soon as possible. But I can make no promises when this is going to happen.

Unfortunately, I can only suggest you to either allow this pages or watch the embedded prezi with an alternative browser until this issue is resolved.

Kind regards,
Nicki

still. :frowning: