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GitHub User: gwert
I was able to get everything working, but I've discovered a quirk that I can't seem to figure out. When you click sign out, the fb-root div inserted by facebook.js.coffee.erb disappears. That means if you sign in again immediately, you'll be redirected to Facebook instead of getting the pop-up window. Reloading the page makes it reappear, but it would be nice to get it to behave consistently. I'm using rails 4 if it matters.