When the Queen spits out spider webs, they’ll phase through all items in a workshop map regardless of whether collision is enabled.
The ghosts’ orb projectiles also phase through items. I initially assumed this was intentional given that ghosts tend to phase through surfaces, but the orbs actually do collide with surfaces in the official maps.
Notes / Media
While testing this bug, I tried to check whether the Queen’s acid glob attack also passed through items, but she actually never did it, even when I fought her in an official map (Acrophobia). Not sure if that attack is bugged or I just got extremely unlucky.
Queen spider webs: