When testing an entity's 'OnGround' nbt data while they are standing inside certain blocks such as; cobwebs, berry bushes, and powdered snow, the game will return an inconsistent value at a fairly consistent rate.

Steps to Reproduce:

1. Run the following command in a repeating command block
   ^{(The player's name will be printed in chat if they are NOT on the ground)}

   /say @a[nbt={OnGround:0b}]
   

2. Stand inside one of the following:
   → Cobweb
   → Berry Bush
   → Powdered Snow
3. Jump, and wait to return to ground level

Expected & Observed Results:

- The values printed will primarily be empty messages, but on occasion the player's name will be printed (indicating that the return value was false). This happens at a fairly consistent rate.
- The messages displayed in chat would always be empty messages, as the player is on the ground.

Screenshots/Videos:

2023-10-13_17-01-50.mp4

Notes:

Moving around inside the block will actually negate the observed behavior. The player must be standing still for the inconsistent result.