The Bug

Powder snow doesn't drip into a cauldron like water or lava does. (although understandably snow works differently than those fluids)

How to reproduce

1. Place blocks in the air to form three holes
2. Place a lava, water and powder snow source block into the holes using their respective buckets
3. Place a pointed dripstone on the underside of the blocks at the bottom
4. Place a cauldron underneath each dripstone (see construction in screenshot)
5. Optionally run for instance this command:

   /gamerule randomTickSpeed 10000
   

   → After waiting several minutes, notice the cauldron underneath the powder snow never gets filled, while the others do