Fishing rod bobbers have always been an unnamed entity, and when searched for by the game, are referred to as the "unknown" entity. Using the name "unknown" in the type= field of a target selector allowed players to target fishing bobbers anyways.
However, in the 1.11 snapshots, although still referenced as an "unknown" entity, target selectors will no longer accept "unknown" as a valid entity ID. This is likely due to the renaming of Entity ID's back in 16w32a. Fixing this bug would involve simply giving the fishing rod bobber a proper ID.
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Comments 3
That's my point, Fvbico - rods not having an entity id IS A BUG
And now they can't even be selected with commands
@@unknown It's not a bug, see the resolution for MC-47832.
"unknown" isn't a type, it's a display name (which is also dependent on your language and always has been). You would use @e[name=unknown] to try selecting it, not @e[type=unknown].
Fishing rods don't have an id, they never had.