Related to MC-610 (may be this bug is duplicate of it). But in this bug, half floating tall grass generate in deep dark Single Biome world.
Steps to Reproduce:
Step 1: Create a world with World Type: Single Biome, set it into Deep Dark.
Step 2: When spawn in, look around for half floating tall grass (while looking for them, you may find grass on sculk, see MC-256102 for more info)
Observed Results:
There are half floating tall grass.
Expected Results:
There aren't half floating tall grass.
I can confirm this behavior, though I believe this is just the same as MC-252435 but instead with tall grass. Maybe MC-252435 could be updated to reflect that this affects more decorations than just pointed dripstone?