When using the named crossbow in the offhand and a different named item in the main hand, the crossbow is not shown in the death message but the item in the main hand instead.

Steps to Reproduce:
1) Go into creative and take a crafting table, a stack of gunpowder, stack of paper and a stack of white dye

2)Craft the 3 stacks of ingredients into firework rockets using the crafting table

3)Get an anvil and rename a crossbow to "Item1" and rename a wooden sword (can be any item) to "Item2"

4)Set game mode to survival and reach a health of 0.5 hearts

5)Charge the crossbow with a rocket by placing the rocket in the offhand, crossbow in main hand and holding right click

6)Go into an enclosed space and put the charged crossbow in the offhand and renamed sword in main hand and right click facing down

7)Observe the incorrect death message showing that the firework was fired from "Item2" instead of "Item1"

Observed Results:
According to the death message, the firework was fired from "Item2" instead of "Item1" which is wrong

Expected Results:
The death message to say that the firework was fired from "Item1" instead of "Item2"