Thread:Project:Support desk/external link syntax without mentioning http

Since when did MediaWiki support an external link syntax like this without mentioning "http" ?

You type:  [//harrywood.co.uk] 

You get: [//harrywood.co.uk]

Couple of things about this. I can't see it mentioned on Help:Links. If it's an intended feature I guess it should be added?

Does this work properly with some external link control mechanisms such as MediaWiki:Captcha-addurl-whitelist   I could be wrong, but it doesn't seem to work on our wiki. We're seeing captchas always appearing for links done in this style. )