With many sites supporting but not requiring HTTPS now, there's an increase in protocol-relative links. A protocol-relative link is one where the protocol is not specified, and the browser redirects to HTTPS if the page containing the link is viewed as HTTPS, and redirects to HTTP if the page containing the link is viewed as HTTP. For example, this link is protocol relative; if you hover over it you'll see the same protocol as however you're viewing this question. How do search engines parse protocol-relative links? If the Googlebot is crawling a page via HTTP, will it remain in HTTP when following protocol-relative links, or will it know to look at both the HTTP and HTTPS versions of the target link?
How do search engines handle protocol-relative links?
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