The UI design is better, and it would be even better if the domain name can be copied.

Nice design, better than IPvFoo

It works! Fun to see which websites support IPv6 and which don't.

This is the best and most unobtrusive IPv6 indicator for Firefox. I especially like that it's completely open source.

Not only shows IPv6 connectivity, but lists apis and called web modules on the site. Very useful for evaluating IPv6 content and content providing.

Very simple, but it is good to check IPv6/IPv4 connection.