I discovered an inventory duplication bug that occurs when using '/data merge entity' on a villager. I have attached a datapack to use as an example, but the bug is not limited to only this datapack.

To Reproduce:
1- Spawn new villager
2- Give villager 1 stack of carrots
3- Run '/data get entity' to confirm 1 stack of carrots in inventory
4- Nametag the villager "silence me" to trigger datapack function that runs the following command:

execute as @e[name="silence me"] at @s run data merge entity @s {CustomName:"{\"text\":\"silenced\"}",Silent:1b,ActiveEffects:[{Id:24b,Duration:5,ShowParticles:0b}]}

5- Run '/data get entity' to now see 2 stacks of carrots in inventory
6- Repeat steps 4 + 5 and you will now see 4 stacks of carrots in inventory

Everytime '/data merge entity' is run on the villager, the inventory doubles.