User blog comment:Kirkburn/Technical Update: April 13, 2015/@comment-452-20150418194704/@comment-452-20150423130223


 * This explains how they were able to “… see the breakdown of which email recipients use clients that can’t view rich text”.

No, it does not.

They have no way of knowing if I have clicked a plain link in a plain-text email: the link has no tracking and the referrer field is blank in the HTTP request.


 * They can breakdown which users definitely view HTML emails, and guess from the remainder - which might also include people who just don't check those emails.
 * I personally normally use the email notification and a reminder to check Special:RecentActivity, and only sometimes click the diff link in the email.
 * They can guess, that a user visiting a page after an email has been sent might have clicked the link.

Furthermore, since all my emails are also forwarded to a gmail account, I sometimes check my Wikia emails through my gmail account, and click the links in those emails - which do have a referrer, and may have recorded me as "someone who can view HTML email.

The only other emails I get which don't support plain-text are from spammers, and amateurs, so I'm not sure why Wikia would want to emulate either of those.