The email button coming and going would be because of the login coming and going so that makes some sense given the basic problem.
If you aren't having any stalls with modern view page displays, I'd be tempted to think the problem is the cookie is getting cleared by something. The private browsing option does that, you don't by chance have that turned on. It's purpose is to clear out any traces of where you've been which includes history and cookies. But something is making that new Yesterdaystractors.com cookie get removed after either time or session expiration.