1x2_a7 is a structure of Woodland Mansions which is supposed to generate with 11 red mushrooms and 10 brown mushrooms. I noticed in 1.14.4 that some mushrooms were missing during generation. I thought it was a rare case and did not report it.
Recently, I started several new worlds and discovered that 1x2_a7's are not generating mushrooms at all. The followings are some examples:
1. Seed: -6991895562573809762
World Type: Normal
Coord: 374 68 134
2. Seed: -6991895562573809762
World Type: LB
Coords: 1883 69 758, and -1012 69 -11241
3. Seed: -126790419721262898
World Type: Normal
Coord: 4579 70 3294, and 324 68 8004
Duplicate of MC-160169