Slime Texture Does Not Animate When Idle in Flat World

Steps to reproduce:

1. Create a new Superflat world.

2. Spawn a slime (any size).

3. Observe the slime when it's idle.

Expected Result:

The slime should have its usual animated texture, even when standing still (idle), showing its "pulsating" motion to indicate it's a living mob.

Actual Result:

The slime appears as a completely static block with no animation, making it look like a green translucent cube. It appears as though the texture isn't updating when idle.