Fish magically gain momentum and bounce up to 10 blocks in the air on slime blocks

The bug

If any fish is on a slime block, it will start bouncing, and slowly start accumulating momentum until it bounces ~10 blocks high every time.

How to reproduce

1. Summon a square of slime blocks below your feet

   /fill ~-3 ~-1 ~-3 ~3 ~-1 ~3 minecraft:slime_block

2. Obtain a cod, salmon, pufferfish, or tropical fish spawn egg
3. Spawn the entity of your choice on top of the slime blocks and watch it closely
4. Take note as to whether or not fish illogically gain momentum when bouncing on slime blocks
   → Fish illogically gain momentum when bouncing on slime blocks

Expected behavior

Fish would not be able to illogically gain momentum when bouncing on slime blocks.

Examples

Here are some examples in videos:

• 2019-10-21 15-44-14.mp4
• Minecraft 1.14.4 2019-10-22 18-39-25.mp4