Mobs' Collision Box not matching with Bedrock Edition

In Bedrock Edition version 26.20.22, the update logs indicate that collision boxes of certain mobs were modified to align with Java Edition standards. However, for specific mobs including pandas, piglins, and squids, the Java Edition has not yet implemented corresponding collision box changes. This discrepancy creates an inconsistency where Bedrock Edition has partially updated mob hitboxes to match Java, but Java's values remain unchanged, leading to a de-sync. This bug report is created to track and manage the collision box differences between the two editions. (relates to MCPE-236077)

How to Reproduce:

1. In Java Edition (2026 drop1), press F3+B to enable collision box visualization. Observe and record the hardcoded width and height values for the listed mobs from the game files.

2. In Bedrock Edition (version 26.20.22), navigate to the behavior pack directory: behavior_packs/vanilla_1.26.20/entities

3. Locate the JSON files for the target mobs and check their collision_box parameter values.

4. Compare the Bedrock Edition values with the recorded Java Edition values.

5. Verify in-game using trapdoors and block placement to visually measure and confirm the collision box dimensions in both editions.

Observed Results:
The collision box dimensions of the following mobs in Java Edition 2026 drop1 do not match Bedrock Edition 26.20.22 values:

Expected Results:
The collision box dimensions of these mobs in Java Edition 2026 drop1 should match Bedrock Edition 26.20.22 values.

Additional Notes:
Some of these discrepancies may not require fully synchronization — for instance, hoglin and zombie hoglin in Java Edition are intentionally given smaller dimensions to fix some collision related issues, while Bedrock Edition retains larger dimensions that are pretty much identical.