Cannot write on signs when they are placed on fences

Cannot write on signs when they are placed on fences:

I placed a sign on the side of a wooden fence and I expected to be able to write a text on the sign.

What actually happened was I placed the sign, but the text writing interface did not come up, and it placed a blank sign.

Steps to Reproduce:
1. place a wooden fence
2. place a sign on the side of the fence