There is no preview when holding left click in the inventory to distribute a stack into multiple locations.

[IntegratedQuantum]

This has been removed in 3a4a695e3ddc46eeac44b6467b127c8ac0b4c0cb to push for a better inventory interface. This preview must not modify the actual inventory data, which could lead to synchronization problems. This could be fixed by introducing a preview ?ItemStack to the ItemSlot that gets prioritized over the actual data from the inventory when present. The relevant code is in gui.zig in inventory.update()