The probability that footnotes could be added to a social media post* whilst retaining meaningful content in at least 2 component parts is proportional to the number of available characters per new post but tends towards zero below 256.
Barrie Turner. (@bazbt3)
Version 1.0, 2015-03-09.
*The separation between email, social media posts and instant messages is not as rigid as in the Internet's infancy. The word 'post' is used here both for brevity's sake and to limit this document's terms of reference.