Even if the ISP does everything right, there are a lot of small sites with broken IPv6 setups caused by incorrect server and DNS configurations. While my ISP ap

Even if the ISP does everything right, there are a lot of small sites with broken IPv6 setups caused by incorrect server and DNS configurations. While my ISP appears to provide a solid IPv6 setup, I've ran into quite a few issues with sites either: - Serving different content on IPv4 vs. IPv6, e.g. just showing Apache2's "It Works" page - Serving some subresources behind a reverse proxy on IPv4 only (and 404ing on IPv6) - Forgetting IPv6 AAAA Records after a server change Trying to debug this as a user is annoying and even if I identified the issue before leaving the site, working with sites to get it fixed has been an issue. I quickly ran into the "Works for me" issue, when the administrators (and a majority of their users) ran on IPv4 only networks. Ultimately I just disabled IPv6 on all my systems because it ends being more trouble than it's worth.