The string representation of NBT integer arrays always has a trailing comma after the last entry. This is different to NBT lists.
- Use the following command
- Throw the item on the ground and inspect its NBT data
→ You will see that the last item in the integer array has a comma behind it
Based on 1.11.2 decompiled using MCP 9.35 rc1
The method net.minecraft.nbt.NBTTagIntArray.toString() adds a comma even for the last item.