Cave vines are floating after explosion

The Bug
Cave vines can be left floating after a TNT explosion

What I expected to happen was...:
An explosion should destroy the cave vines too by breaking the lush cave ceilings.

What actually happened was...:
The cave vines haven't been destroyed

Steps to Reproduce:
1. Find a lush cave.

2. Sommon a big explosion beside it. Make sure the explosion cannot be loaded very quickly.

3. Try to find the strange cave vines.