When giving the player a music disc with a higher max stack count than default (1) eg. command: (/give @s minecraft:music_disc_13[minecraft:max_stack_size=99] 99) and then inserting the said music disc stack into the jukebox, it copies over the whole stack into the jukebox while only shrinking the stack size of the disc by one. When taking out the disc by right-clicking the jukebox, you duplicate the said stack.

My proposed solution is calling{{ ItemStack.copyWithCount(1)}} instead of ItemStack.copy() }}in the RecordItem class in the useOn method when calling the {{setFirstItem method in JukeboxBlockEntity class. (mojmap)

I have implemented this in a mod form, as I encountered this bug before but it was a none vanilla issue, with the new item component changes, this is an issue that can be run into in a vanilla environment so I felt the need to report this.