I updated directly from 20w20b to 20w22a and Nether Fortresses, Ocean Monuments, Pillager Outposts, and Witch Huts all work as intended. Seems to be an issue with corruption caused by 20w21a.
Occured to me as well with a dark oak sign in singleplayer.
I updated directly from 20w20b to 20w22a and Nether Fortresses, Ocean Monuments, Pillager Outposts, and Witch Huts all work as intended. Seems to be an issue with corruption caused by 20w21a.