When bonemealing a small dripleaf plant, it can destroy blocks, including obsidian and bedrock. The blocks don't drop, they're just deleted.

To reproduce

1. Place a small dripleaf plant on a clay block
2. Place a block above it
3. Apply bonemeal to the plant
   → The block is broken

Might require several tries to reproduce if the plant doesn't grow tall enough.

Video

Minecraft 21w05a - Singleplayer 2021-02-03 20-15-58.mp4