https://addons.mozilla.org/en-US/firefox/addon/269246/<p>I was looking for something like this, but could not find any (let me know if there are any good alternatives). Once you enable this addon, all requests to facebook will be forwarded to their https counterparts.<p>Please let me know if you run into any issues or if there are any glaring mistakes in the approach.
HTTPS-Everywhere is a Firefox addon created by the EFF which does the same thing. But it's not limited to Facebook, there are currently rulesets for hundreds of different websites.