Last modified: 2006-05-13 19:30:10 UTC
The external link syntax
only does autonumbering for http: and https: URLs, as tested on the MediaWiki sandbox
(http://meta.wikimedia.org/wiki/Meta:Sandbox). For other schemes, the syntax above gets rendered
without autonumbering, as if using the inline target syntax without the brackets.
The MediaWiki handbook's section on external links (http://meta.wikimedia.org/wiki/Help:URL)
provides no information on which schemes have auto-numbering support. It reads:
<tt>A link in external link style can be of the forms:
target: http://meta.wikimedia.org/ is rendered as http://meta.wikimedia.org/
[ target label ], with a blank space in between: [http://meta.wikimedia.org/ wikimedia] gives
wikimedia (see also Help:Piped link)
[ target ] - these are automatically labelled with serial numbers 1, 2, 3, ...:
[http://meta.wikimedia.org/] gives 
The target is a URL which can start with "http://" or "ftp://";</tt>
This description would at a minimum lead to the expectation that autonumbering should apply to http
and ftp, which is not the case.
Personally for my use I would like ftp links to be auto-numbered as well. I don't understand why
auto-numbering shouldn't be uniformly applied to all supported URLs.
(Aside: I'm unable to determine what version of MediaWiki the meta.wikimedia.org website uses,
hence "unspecified version" is entered for Version field of this bug report.)
Version 1.7alpha (r14131) as of this moment...hope I'm doing this right...
Fixed in r14202.
[ftp://foobar] is autonumbered.
ftp://foobar is still a free link.