I don't know how much refresh rate is more likely to drop on Facebook and Co, but it is generally known that if you have your cell phone at 120 Hertz and you open your normal camera App, then it drops down to 60 Hertz. They have to work at a low refresh rate, because of heating issues that could be the reason why. There is no camera app on Facebook, viber, Snapchat, Instagram where you see it above 60 hertz.
