This is a test for Happy Eyeballs. It will repeatedly attempt to load, via this browser instance, a randomly named dual stack javascript resource. Below you will see counters of how often IPv6 is used, IPv4 is used, or both fail.
Note that if you move this tab to the background it will run for up to just 3 hours. Bringing it to the foreground will resume the test.
Simple requests may be sent to jfesler@test-ipv6.com for consideration. Pull requests more strongly considered, see the GitHub repo..
The canonical location for this test is now he.test-ipv6.com. Old URLs will be used for developement purposes.