The small chest which can be applied to donkeys or mules has two front faces. This is unlike the llama's chest texture, which has a front and a back texture for both chests on the entity model.
While generally issues regarding model faces that cannot normally be seen are resolved as "Won't Fix" due to the minimal gain from fixing the issue, this might be worth fixing due to MC-268985. If the chests were changed to wobble again, the back face may be visible again.

Steps to Reproduce:

1. Apply the provided resource pack:
   DonkeyChestFront.zip
2. See if the back face (which is not modified) is ever used
   

Observed Behavior:

Only the front face of the chest (which was modified to be red) will be visible, facing outward.

Expected Result:

The back face of the chest would not have a latch on it, but instead would appear as a back face similar to the llama's texture:

Screenshots/Videos:

The donkey's texture currently:

Suggested Fix:

Notes:

1. MC-274258 is also relevant to this report. The horses contain this texture too, but were not included in the report, because they do not actually use the texture at all.
2. Also related to MC-94829 MC-274259