Do you have any evidence to say that this is the case other than speculation? It's also possible that they just changed the URL format. FWIW `pfbid` seems to be a shortened version of "post fb id" so why would it include the "cl id"?
OP: https://www.facebook.com/VICE/posts/pfbid02XdVziPTwhmPU9XzBq...
Me: https://www.facebook.com/VICE/posts/pfbid0TbuHEaGP2fLTRDFRTu...
There were also a bunch of other query params junk after that I omitted here for brevity.