Some mails our wiki sends out are http. This can e.g. be tested by requesting a password reset mail. "Someone (probably you, from IP address [removed]) requested a reset of your password for Gentoo Wiki (<http://wiki.gentoo.org/wiki/Main_Page>)." Given our Wiki is HTTPS only (all HTTP requests are redirected) this should be changed. MediaWiki has a $wgProt and $wgDefaultPort option that may be at fault.
This should be fixed. Please test
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