Probably already a well-worn word or phrase for this, but what do you call it when you've read something online which disappears ? Not like a dead link or "site not found", but an erased posting or story.
For instance, when I've seen a tidbit of snarky dialogue on ibrattleboro, I've gone back to look for it later and it's been removed. There's no sign the offending text was ever there, and I question the accuracy of my own memory.
I'm not making a value-judgement about when such actions are called for. Just pondering the notion-changing the past, courtesy of seamless editing.
News/media "offline" (print/broadcast) has retractions & corrections-the snafu is still there, though.
Perhaps I'd label this online phenomena "phantom thread"? Please contribute your ideas on the concept, as well as a neologism with which to name it.