How to rewrite absolute URL link in http response

You should use the Developer tools in the browser (F12) to see what is not being converted to https references. Some of the "; references may be in files that do not have a "text" content-type.

I've also seen webservers return references like

http:\u002f\u002f

Finally, I usually recommend that you stream replace entire domain references, but that is up to you.

STREAM::expression {@http://mydomain.com/@https://mydomain.com/@ @http:\u002f\u002fmydomain.com/@https:\u002f\u002fmydomain.com/@}

YMMV