🔖 This is a technical write up of a visual bug in the Boston Airport area, specifically 12, -2 also known as BostonAirportExt05 in the Commonwealth. If you have either PRP or PRP Lite (Boston Airport module) installed, you have this fixed already. This write up is intended for forwarding to the BGS master file and eventually have it patched so that PS4 users can have it fixed at some point in the future if precombines/previs for the area are rebuilt.
The Boston Airport has a fence has a quirk in the game where if you look at roughly the center and above it, the game seemingly treats it as an invisible wall. The fence is actually a red herring, as the actual problem lies with a set of objects that show up when the player have progressed enough in the Brotherhood of Steel questline so they show up at the Airport.
A BOSBarricadeWallPlatform01 object (the main fort like thing with the flag attached, ID 1AEEE0) has a pair of invisible walls or PlaneMarker references neatly sandwiched inside to help with render performance in the area, which is fine for what they do, but the two markers, with the IDs 1AEF1A and 1AEF19 didn't get tagged properly. The two planes should have BoSBase (XMarker) in their enable parent, otherwise they get considered in the occlusion calculations as part of the previs or umbra processing the game went through in Sep 4, 2015 (as per the master file's generation dates) and any future generation without the fix implemented.