Hostname canonicalization has surprising interactions

[jeremyroman]

What is the issue with the URL Pattern Standard?

This has been noticed at least twice now and probably merits its own issue:
#239 (comment)
#258

Most notable, hostname parts that look like IP addresses can end up being canonicalized into full IP addresses in ways that are surprising and nonsensical, like 192.168.* expanding to 192.0.0.168.* (because technically 192.168 is a valid IP address notation).

As noted in the comment, the same is true of port, but it's harder to discover how to work around it for hostnames.