Comparator measuring a double chest does not update when copper golem adds/removes items in the opposite side

When a comparator measures one side of double chest, items placed inside by players, hoppers, etc. will be detected by the comparator regardless of where they are placed in the chest inventory.

However, when a copper golem adds items to a large chest, or removes them from a large copper chest, the comparator does not update if it is measuring the “other half” of the chest.
For example, if a golem places an item stack in the top left inventory slot (or anywhere in the top half of the large chest inventory), this will not update a comparator detecting the ‘right side’ of the chest.

Steps to reproduce:

1. Place a double chest with no contents.

2. Place a comparator attached to the ‘right’ side of the chest, along with anything you wish to measure redstone output.

3. Spawn a copper golem and copper chest.

4. Place items in the copper chest, and allow the copper golem to add them to the double chest.

5. Observe the lack of comparator output.
   

Note that this behaviour does not apply to trapped chests, because the redstone signal they create on being interacted with gives the comparator a block update.

Video footage and further explanation is provided below:

https://www.dropbox.com/scl/fi/1gl5a78bb9yg2752wb6g2/Copper-Golem-Comparator-Bug.mp4?rlkey=m2jcgcor3imtdhqtnm1pj5ssr&dl=0