Opening your inventory when riding some mobs while continuously modifying its data will make the GUI flash

If you a command block that repeatedly modify a or some data of a donkey, a mule, a llama or a trader llama and then ride one of them then press E, the UI flash for a short time.

Affects:

1. Mule

2. Donkey

3. Horse

4. Llama / Trader Llama

Steps to Reproduce:

1. Summon one of the listed mobs, and tame it

2. Place down an repeating command block with the following command (set to Always Active:

   /execute as @e[type=donkey] run data merge entity @s {a:1}

3. Ride the mob

4. Press E to open your inventory

Observed result: The UI flashes.

Expected result: U still open the UI normally.