LoS bug, see thru wall

[TVDinner]

I finally got this one to replicate in a small module.

Fire up a clean 5E campaign. It probably fails lower in the food chain, but the module was made in 5E.

Load the SRD beastiary and the "LoS Error" module.

Open the "Error map" image.

Drop an orc into the tracker.

Drag the tracker orc to the 4x4 area inside the square on the "place token in here" layer. I usually start in the top right.

Move the token around the 16 squares. FGU will sometimes show through the west half of the south "wall," where the scribble is on the "wall error" layer. Deleting some of the other wall points that are outside that area can "fix" the bug.

The real image layer was replaced with an FG battle map that is not the same size. The wall lines are single and there's a little stub between the two adjacent secret door walls to keep them separate (hmmm).

I have the logs if you really want 'em, I didn't see anything in there. Windows 10. Default NLS stuff.