Why not just use a browser plugin that allow you to disable v6 selectively on a per site/domain basis? Most of them just display v4/v6 information, but 4or6 allows you to quickly set a domain/site as v4 only. Ref https://addons.mozilla.org/en-US/firefox/addon/4or6/?src=search -- Hugo On Oct 25, 2014, at 10:26, "Matthew Kaufman" <matthew@matthew.at<mailto:matthew@matthew.at>> wrote: On 3/17/2014 11:43 AM, Matthew Kaufman wrote: Random IPv6 complaint of the day: redirects from FCC.gov<http://FCC.gov> to pay.gov<http://pay.gov> fail when clients have IPv6 enabled. Work fine if IPv6 is off. One more set of client computers that should be dual-stacked are now relegated to IPv4-only until someone remembers to turn it back on for each of them... sigh. Matthew Kaufman Still broken, 7 months later. And again, I was too busy trying to pay to try to pull a full set of logs. But if you do something on the FCC site that requires payment, the redirection flow dies halfway through if you're coming from IPv6 and works fine if you turn it off... so yet another computer in the house has IPv6 disabled until manually turned back on. Matthew Kaufman