enable jquery load cross domain with a proxy

Question

I have two resources. A standard apache website on mycooldomain.com and a node website on mycooldomain.com:4337. On the apache vhost I have defined a proxy so that i can reach node using mycooldomain.com/myapp.

Now what I am trying to do is to have this code working in mycooldomain.com/index.html:

$('#somediv').load('/myapp');

but this will end with the browser blocking the request marking it as "insecure". I assume that the proxy should be the workaround to put the two requests on the same domain but as far as I can see I am missing something.

My proxy definition in apache is the following:

ProxyPreserveHost On
SSLProxyEngine On
ProxyPass /myapp https://mycooldomain.com:4337
ProxyPassReverse /myapp https://mycooldomain.com:4337

What am I missing?

I also tried to add to this:

Header always add Strict-Transpor-Security "max-age=15552000; include subdomains"

the following line:

Header set Access-Control-Allow-Origin "https://mycooldomain.com:4337"

but this didn't solve the issue either. Any hint?