In the debug world, a world meant to display the different block states for all blocks, the snow block, which only has one block state, appears twice.

To replicate:

• Create a new debug world in 1.16.1
• Go to 59 70 263 and 61 70 1. These two coordinates both have snow blocks despite there being no difference in block states.

Edit: I just noticed, this applies to more than just snow, and this issue has been reported before.