I connected Facebook via the settings page in my Foursquare account. I enabled the default option to post checkins to Facebook. I checked in via Foursquare on my phone. I made sure that the Facebook sharing option was enabled. I also enabled the Twitter sharing option. I checked my Facebook. There was no post from Foursquare. I checked my Twitter, and there was a post from Foursquare.
I have disconnected Facebook from Foursquare multiple times. I have logged out of Facebook and Foursquare on my computer, and on my phone. I have reconnected Facebook. Foursquare still does not post to Facebook. I have even gone so far as to create a new Foursquare account. Foursquare still does not post to Facebook.
I tried with Yelp shortly afterwards, and it posted just fine, so it cannot be anything to do with rate limiting on Facebook's side.
I followed the following instructions, precisely, with no effect:
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