That does look very similar. The invalid item being added to the spawned bundle in this (256599) is being done in-game through normal gameplay methods, such as attempting to right-click a stack of chicken into the overfilled bundle, resulting in a stack of (what I'd assume to be) AIR being added to the bundle without the use of a command.
Eclipsebre
That does look very similar. The invalid item being added to the spawned bundle in this (256599) is being done in-game through normal gameplay methods, such as attempting to right-click a stack of chicken into the overfilled bundle, resulting in a stack of (what I'd assume to be) AIR being added to the bundle without the use of a command.