What I expected to happen was...:
The flint and steel should do a swing ( to light fire ) animation in off hand.
What actually happened was...:
The sword in my normal hand swinged in F5 but still lighting the ground
Steps to Reproduce:
1. Put a flint and steel in your off hand.
2. Put a sword in your normal hand.
3. Go to F5 and light the ground.
Dupe of MC-82965