Why do LLMs freak out over the seahorse emoji?

Theia Vogel explores why LLMs insist a seahorse emoji exists (it doesn't). Given Unicode's aquatic menagerie, both humans and models reasonably assume one should exist and a proposal for one was even rejected in 2018. It's the 2025 “strawberry r’s” equivalent: pattern-matching machines generating what ought to exist rather than what does. A collective Mandela effect, silicon and carbon alike.