Thanks for these notes, they are very helpful! Just a remark about the quote from Ryan Lane's blog post ("All resources should be referenced using protocol-relative URLs now"): As the preceding sentence indicates, this does not refer to external links, but to resources that are displayed/used within the page and are loaded together with it (e.g.
<img src="//bits.wikimedia.org/images/wikimedia-button.png" ...</img>). These would cause a mixed content warning in a HTTPS page when hard-coded to HTTP. The same concerns do not apply to external links. Regards, HaeB (talk) 18:47, 4 May 2013 (UTC)