I was playing survival 1.15.1 and I had placed some spruce signs on a bed (like as a siding decoration thing) and i wanted to move it, so i destroyed the bed and only got 1 sign back. there were 2 signs on the bed originally. I went into creative to test it out. I placed two signs on the side of the bed, which was one on the head block of the bed and one on the end block of the bed, as in two different blocks. If i broke the head block of the bed, the sign on the head block would pop off, but the sign on the end block wouldn't. same visa versa.

What I expected to happen was...:
both signs to come off the bed 

What actually happened was...:
only one of the signs came off and the other magically disappeared

Steps to Reproduce:
1. place bed and place one sign on the left or right TOP half of the bed and then one sign on the left or right BOTTOM half of the bed
2. If you destroy the TOP half of the bed, the sign that was placed on the top will pop off, but the other sign will not and will just disappear