Spider spawning in 1x1 area
I noticed you have all the tickets for this bug marked as resolved. But it is not fixed, it is happening right now!
Spiders are spawning on a 1-block space, specifically in my Creeper farm.
I was recording this on video and I will provide screenshots.
My Creeper farm uses platforms with this pattern: block->block with button on it->block->block with button on it, and hole in between, repeating! With trapdoors overhead. So the only spaces for a mob to spawn are 1-block!
See the images I have attached!