When leaving and rejoining the world with a health boost effect, the extra health containers still remain, however the extra health is removed as you are reset back to the default amount of ten hearts.

Steps to Reproduce:
1. Obtain a health boost effect
2. fill any of the extra hearts while the effect is still active (some or all, either works)
3. Leave the world and rejoin
Observed Results:
The world should have saved the amount of extra hearts you had filled up.
Expected Results:
The world does not save the extra hearts, leaving you with the default ten.