Its not a bug but more a fustration with masion spawning.

A fix would be adding a vector generation so that going from spawn (0,0) the game would detect the nearest dark oak forest within a set tolerance of say 7500-10000 blocks and place 1 woodland mansion. That way a player especialy kids with game time restrictions like i did back in the day would actualy have a chance of finding 1 in an hour with a woodland explorer map.

10,000 blocks is crazy enough. I had to travel more than 20,000 to get to my nearest mansion and the loot inside is not worth the distance. Also doing so increased the world size by 60mb