Placing furniture in already build building

I don’t know if I am dumb or something but I find it extremely irritating to place furniture on wall inside an already build building. Each time I try to put a lantern inside a room, there is always one or more walls that keep fading (to let us see the others side). that mean:

  1. I dont see the furniture on those wall meaining some of my work is going to waste

  2. I can’t put stuff on thos wall, preventing me from customising my buildings

A simple fix should be to add another view mode where only the roof of building disappear. It would let us see inside without removing anything inside.