IE/Edge - Loading insecure content without warnings
By using a simple server redirect and a document.write, we can load insecure content (coming from iFrames or any element) on Internet Explorer and Edge, bypassing the classic Mixed Content warning.
Top page in a secure page (https:), iframe does a server redirect to an insecure page (http).
Inside the insecure page we do a single document.write() and bingo!
Now we can freely use the iFrame load insecure content without warnings.