After signing up to join this forum I received the usual account confirmation email message. The hyperlink in the message took me to a page with a button, “Click to activate your account”, which I clicked on. The page that then appeared was blank except for [“BAD CSRF”]. This was using Chrome Version 61.0.3163.91 (Official Build) (64-bit) in El Capitan.
I pasted the same link into Safari and the activation button worked there.