villager duplication

when I put a villager I captured in a boat onto a glass block, the villager gets duplicated onto the glass block as a entity with no AI. if I move the boat away from the glass the "ghost" disappears, though I cannot get this to happen within a creative world, it happens not only in one location but on any glass block that I use within my survival world.

the "fake" villager is solid, and though I cannot attack it, it has a hitbox and can be set on fire. the fake villager can also be moved by pistons and is tracked by zombies as a real villager.

I have all of my farms within 150 blocks of the area where the glitch is occurring (my base) though I don't believe that lag is responsible for the glitch

I lack the technical knowledge to give anything more than that.