Placing a sign that was in a stack of 1 causes it to lose it's data

When you ctrl+middle mouse on a sign, it is supposed to give you a sign with the NBT tag of the original sign you selected. On this new snapshot, the signs aren't duplicated. Also, I switched my world back to 1.10.2 after I saw this, and all my signs disappeared. Only their black outlines are there when I hover over where the blocks used to be. Please help!