Why do I see a message asking if I want to see the page hosted on HTTPS?
When viewing a webpage remixed with X-Ray Goggles, you might see a banner at the top of the page asking if you want to see that page on HTTPS.
This happens when you remix an http://... web page, as opposed to an https://... web page.
HTTP is the language that servers and browsers use to negotiate data transfers, and HTTPS is the secure version. Because we care about secure communication at Mozilla, we aim to host all of our content over HTTPS, but we make an exception in the case of certain Goggles remixes.
This is because of what's referred to as the mixed content problem. Large parts of the web still use HTTP. So even if a page is being served on HTTPS, it might include resources that are served on HTTP — for example images or videos or styles — and now the browser will refuse to request those resources. Instead it will give you a warning about "mixed content," and the resulting page will look broken.
Rather than show you a remix that looks broken, Goggles will give you a URL that starts with http:// if the original page used HTTP. This way your remix will always look the way you expect it to.
However, we also want people to understand the difference between HTTP and HTTPS, so when you visit a remix that starts with http://, the remix notice bar at the top of the page also contains a link to the https:// version --same page, just served using HTTPS instead of HTTP-- so that you can see exactly how bad things get if you can't control which protocol gets used for resources on a page.