levers placed on stairs/half_slabs disappear when updated

Put the summary of the bug you're having here

I thought the lever would stay there when I placed something next to it or activated it

But instead when I placed something next to it or activated it it disappeared

Steps to Reproduce:
1. put lever on stairs/half_slabs
2. update it (activate it or place block next to it)
3. watch it dissappear