Prior to the 1.13 snapshots, straight walls that connected to only two opposing sides would keep the same smaller collision box regardless of if there was something placed on top of them or not. Now they expand to match the rendered size. It's possible that this is intended however this also means that if a player is up against it when it expands, they glitch into it a bit if they try to push forward.
Comments 5
Affects 1.16.4 but in my opinion should be marked as WAI, as when the Cobble Wall render extends, the hitbox does too.
This is expected, and likely intentional behavior. Considering the 'pillar' model of the wall has collision matching it's hitbox when present alone, the collision should be preserved when that model part is used elsewhere.
This can be backed up by MC-122195 which fixed both the cauldron and ender portal eye to have both their collision match with their visual appearance.
Are you referring to cobblestone walls?