If you spawn tentacles(wickerbottom's book) near a wormhole, they will disappear after you jump in.
a gif demostrating: https://imgur.com/BFwNesf
edit: I recorded this gif on BETA Version, but it also happens outside of it
1. Spawn tentacles near a wormhole using the wickerbottom's book.
2. Jump in wormhole.
3. Jump back in wormhole.
4. See that tentacles are gone.