Sources used:

• uri_validate.py, with changes to the userinfo and to IPv6address regular expressions.
• useragent-results/refimpl

Each of the difference noted below should be categorized as follows:

1. RFC 3986 is wrong
2. uri_validate.py doesn't match RFC 3986
3. URL Living Standard is wrong
4. URL reference implementation doesn't match URL Living Standard
5. Scripts used to gather the results has a bug
6. Intentional difference between URL Living Standard and RFC 3986

Currently conforming URLs that are not valid URI references

Excluding URLs containing non-ASCII characters

• "\t :foo.com \n"
• " foo.com "
• " \t"
• ":foo.com/"
• ":"
• ":a"
• ":/"
• ":#"
• ":23"
• "::"
• "::23"

Bug 27687 is open to make all of these cases non-conforming.

Valid URI references that are non conforming URLs

• "http:foo.com"
• "http::@c:29"
• "http:/example.com/"
• "ftp:/example.com/"
• "https:/example.com/"
• "gopher:/example.com/"
• "ws:/example.com/"
• "wss:/example.com/"
• "http:example.com/"
• "ftp:example.com/"
• "https:example.com/"
• "gopher:example.com/"
• "ws:example.com/"
• "wss:example.com/"
• "http://192.0x00A80001"
• "http://user:pass@/"
• "http:/example.com/"
• "ftp:/example.com/"
• "https:/example.com/"
• "gopher:/example.com/"
• "ws:/example.com/"
• "wss:/example.com/"
• "http:example.com/"
• "ftp:example.com/"
• "https:example.com/"
• "gopher:example.com/"
• "ws:example.com/"
• "wss:example.com/"
• "http:@www.example.com"
• "http:/@www.example.com"
• "http:a:b@www.example.com"
• "http:/a:b@www.example.com"
• "http::b@www.example.com"
• "http:/:b@www.example.com"
• "http:/:@/www.example.com"
• "http://user@/www.example.com"
• "http:@/www.example.com"
• "http:/@/www.example.com"
• "http://@/www.example.com"
• "https:@/www.example.com"
• "http:a:b@/www.example.com"
• "http:/a:b@/www.example.com"
• "http://a:b@/www.example.com"
• "http::@/www.example.com"
• "http:a:@www.example.com"
• "http:/a:@www.example.com"
• "http:@:www.example.com"
• "http:/@:www.example.com"
• "http://ExAmPlE.CoM"
• "http://%ef%b7%90zyx.com"
• "http://%ef%bc%85%ef%bc%94%ef%bc%91.com"
• "http://%ef%bc%85%ef%bc%90%ef%bc%90.com"
• "http://%25"
• "http://hello%00"
• "http://%30%78%63%30%2e%30%32%35%30.01"
• "http://%30%78%63%30%2e%30%32%35%30.01%2e"
• "http://192.168.0.257"