App on Facebook secure canvas URL not loading

Question

The site that I am embedding for my app on Facebook is SSL enabled and hitting the https page on a normal browser brings up the site as expected. For now, my SSL certs are self-signed.

However, when I try to run the app on Facebook, it fails to load the page. There are no errors except the image below. Mouseover on the icon shows a "NULL":

So my question is, does this have to do with the fact that my SSL certs are self-signed? Or is there some other reason for this?

Also, I am not able to check if the non-secure page (http) works on the app as Facebook does not allow me to switch off my secure browsing mode.

Answer 1

After obtaining commercial SSL certs, it now works. So I guess any SSL certs that result in a browser prompt asking the user to continue would not work in an embedded canvas on Facebook.