I have tried numerous times to see if my guardian farm will work. Upgrading from 20w20b to Pre-5 breaks guardian spawns. I really hope this gets fixed. I spent so much time creating my guardian farm and for it to go to waste would be terrible.

Open up the "Brand New World - Copy" file in 20w20b and you'll see that the guardian farm works fine. Guardian farm is at 835 116.

Open up the "Brand new World file in Pre-5 and you'll find that guardians are not spawning.

Links:

Brand New World: http://www.mediafire.com/file/3jwhv9yu0hch23e/A_Brand_New_World.zip/file

Brand New World - Copy:

http://www.mediafire.com/file/39voc3uc2v7qxba/A_Brand_New_World_-_Copy.zip/file