Unable to write signs placed on fences.

When I places a sign on top or on the side of a fence, it just places the sign without letting me write on it.

What i thought and hoped what would happen is that I would be able to write on the sign as one normally is able to do when placing a sign.

What actually happened was the sign placed as blank without giving me the option to write on it.

Steps to Reproduce:
1: Place a fence on any block
2: Place a sign on the fence (anywhere will do)
3: The sign will place without letting you write on it