Non-opaque FOF planes with "holed" textures display opaque in Software when sloped

slopednonopaquebug.wad

added Bug Software renderer labels

assigned to @Lactozilla

changed milestone to %2.2.14

mentioned in merge request !2550 (merged)

closed with merge request !2550 (merged)

mentioned in commit e42f99a0

unassigned @Lactozilla