Issue: two mobs one right click from a spawn egg
Steps to reproduce
Place a creeper spawn egg in one hand and a witch spawn egg in the other hand. Next go to a block of water that is 3 deep and make sure your mouse only hovers over water. Right click on the water and observe two mobs spawning in instead of one.
ActionResult<EnumActionResult,ItemStack> onItemRightClick() --> returns successful in main hand
ActionResult <EnumActionResult,ItemStack> onItemRightClick() fires in off hand --> returns successful in off hand
Two Entities Spawn in(one creeper, one witch) one in each hand.
Solution: if onItemRightClick returns successful don't start the offhand onItemRightClick