Grass blocks located two blocks below dark oak trees aren't converted into dirt when the world generates

The Bug:

Grass blocks located two blocks below dark oak trees aren't converted into dirt when the world generates.

Steps to Reproduce:

• Generate a world with the following seed and teleport to the following coordinates.
• Version: 1.18.2

  Seed: 381794235707411822
  Coordinates: /execute in minecraft:overworld run tp @s -654 70 -91 50 3

• Take note as to whether or not grass blocks located two blocks below dark oak trees are converted into dirt when the world generates.

Observed Behavior:

Grass blocks located two blocks below dark oak trees aren't converted into dirt when the world generates.

Expected Behavior:

Grass blocks located two blocks below dark oak trees would be converted into dirt when the world generates.