Spiders can't see through walls in Minecraft anymore last time they were allowed to see through walls was 1.7.10 before the AI change it has been fixed once in a 1.9 snapshot but it broke again at some point but i went into 1.14.4 pre 5 and i tested with a house without a roof went into survival while it was night time with spiders all around it went into F5 mode and they just stand around and i was safe but i went into 1.7.10 did the same thing and all of the spiders in the area started climbing up and started attacking me i know this is a bug because this is part of their AI to see through walls.