I think it's a pretty hard sell. For extensions, people have to understand why they're installing them. For ad blockers that's pretty easy. No ads! For event signers that's not easy at all. It is extremely hard to explain to someone new to this why they can't log in the way they log in to everything else on the internet and why they need this Chrome extension (and what it does) without losing that someone to a pair glazed-over eyes. And if they don't understand the basics of what the extension is then why are they going to install and use it? They won't. Or they will to please you and then never use it again. That and pretty much everyone who uses social does so cross-device, and extensions in the end just get in the way of actual cross-device solutions.