How can I link from Heroku to github pages via iframe?

Question

My heroku app depends on github pages via iframes, which doesn't work as the browser tells me its Mixed content. So

<iframe src="//larsvers.github.io/tree-of-charts"></iframe>

produces an empty iframe with the chrome console error

Mixed Content: The page at 'https://gradients10.herokuapp.com/project/tree-of-charts' was loaded over HTTPS, but requested an insecure resource 'http://larsvers.github.io/tree-of-charts/'. This request has been blocked; the content must be served over HTTPS.

I assume github's https is not fully fledged so heroku won't point to it. I tried using target="_parent" (as someone suggested on Quora) without much luck.

Would anyone know a fix to this? Or an alternative?

Answer 1

I just needed to be more specific and use

<iframe src="//larsvers.github.io/tree-of-charts/"></iframe>

denoting the path as a directory with a trailing backslash. It seems https (and url naming etiquette) requires this level of specificity...