Files from Commons loading over HTTP
Fragment of a discussion from Support/LiquidThreads
It probably is: I've accessed the page with uselang=en and I had the HTML with HTTP, then I purged it and now it's in HTTPS when you open the page on HTTP. Should be protocol-relative, who files a bug? :) There is bugzilla:32219 but it's only about server to server connections because the thumbs are supposed to be cached locally by the wiki (what about originals like this?).