I've built myself a small image hosting service for my own projects and I recently switched the site to https which works perfectly.
Now I made a .htaccess file with a rewrite rule as described here so if I browse to http://myservice/image.jpg
it automatically redirects me to https://myservice/image.jpg
My question is now how do browsers react, if I embed the http link of an image. Will the rewrite rule still be in effect and the image will be transferred via https or will it use unencrypted http?
I've tested it with Chrome and the image was displayed but I'm not sure if it was transferred via https or http. Are there any case studies which can shine a light on my question?