Links are Rendered Dead on Some Petitions

I’m unable to sign petitions for one site in particular because the links are dead on this browser. They work in IE, but I’d rather sign them without having to go there. Here’s the link to the most recent petition: https://go.berniesanders.com/page/s/this-is-class-warfare?source=em171205-ph-full
I’d appreciate your assistance in this matter.

Thank you,
love.violet