This was an old bug in like 1.8 or 1.9 where item frames, torches, anything that attached to a block would despawn if the block it was placed on was in a different chunk. I don't have an image but I logged in on my world and my tripwire hook had disappeared, at first I assumed someone broke it without me noticing, but checked my debug and the missing hook was in a different chunk.
I was on a small whitelisted vanilla server of 1.12, logs showed no one but the server owner logged in but that was while I was online. Could be a server side issue and not a singleplayer but I don't have the time to test it today.
I know this is probably going to be flagged as duplicate, and it was only one instance of it happening, and I have no proof, but I couldn't find the original bug report for some reason. And I figured I might as well post it instead of staying quiet in case the bug really is back.

Reproducing bug (possibly, it's probably hard to recreate this)
Place tripwire hook (or any item that has to be placed on a block probably) on a block so that tripwire hook is inside the chunk and the block is in another chunk.
Relog or unload one of the chunks
Repeat until it goes missing

Again I'm sorry for reposting and sorry if this turns out to not be a thing.