Heard the word "ephemerality" for the first time. Had to look it up.
Turns out it means almost the same as "temporary". Thanks for upping the vocab.
Has a slightly stronger connotation than "temporary", sort of... extra-temporary, such that it only exists in a fleeting sense. Th term is also used in cryptography: https://en.wikipedia.org/wiki/Ephemeral_key
Well, ya. If content generally vanishes before the DMCA notice arrives via US Mail... ;)