Write on CodeReview comments: "[http://example.com Foo]" and press preview.
Expected: <a href="http://example.com" class="external text" rel="nofollow">Foo</a>
Output: [<a href="http://example.com" class="external free" rel="nofollow">http://example.com</a> Foo]

Enter "Hello [http://example.com] World"
Expected: Hello <a href="http://example.com" class="external autonumber" rel="nofollow">[1]</a> World
Output: Hello [<a href="http://example.com" class="external free" rel="nofollow">http://example.com</a>] World

Enter: "Hello [http://example.com]
World"
Expected: Hello <a href="http://example.com" class="external autonumber" rel="nofollow">[1]</a> World
Output: Hello [<a href="http://example.com" class="external autonumber" rel="nofollow">[1]</a>
World <a href="http://example.com" class="external free" rel="nofollow">http://example.com</a>]
World]

Enter "Hello [http://example.com]
World of MediaWiki"
Expected: Hello <a href="http://example.com" class="external autonumber" rel="nofollow">[1]</a> World of MediaWiki
Output: Hello [<a href="http://example.com" class="external autonumber" rel="nofollow">[1]</a>
World <a href="http://example.com" class="external free" rel="nofollow">http://example.com</a>]
World] of MediaWiki

Version: unspecified
Severity: enhancement