You can no longer shift-right click and split items in the creative menu anymore, nor hold right click and drag items/ hold left click and evenly distribute and drag items. Nor in the creative menu can you shift-left click to delete items from your hotbar. The "x" box in the bottom right corner of my "survival inventory" tab also no longer deletes all/any items in inventory if you double right click on it.
Currently this is all I have noticed as to be a bug in the creative inventory.
I don't know if this is a client side bug for only me, or for others who download and use the 13w24b snapshot from the MinecraftDev Launcher.
Hopefully this issue/bug can be resolved if it isn't just my client.
Thanks!