If you link to a URL with a port number, Markdown will eagerly percent-encode the colon the separates the host name from the port number. See this test message. The chat message I typed in looks like this:
[Test case for bug report about Morkdown](http://example.com:80/)
But the generated HTML (as shown by Chrome's DOM inspector) looks like this:
<a href="http://example.com%3A80/" rel="nofollow">Test case for bug report about Morkdown</a>
[link text](http://x.y#http://a.b)
- I'm trying to see if I can tweak the handling of ports in the outer url, thoughmailto:[email protected]
; there is no version that works on all browsers