Repairing tools does not work in crafting window

[sciwhiz12]

Minecraft Version: 1.16.1

Forge Version: 32.0.57

Logs: not applicable, ingame behaviour issue

Steps to Reproduce:

1. Obtain two damaged diamond pickaxes (/give @s minecraft:diamond_pickaxe{Damage:768s} 2)
2. Put them into the player inventory's crafting grid
3. Observe that there is no crafting result

Description of issue:
In vanilla, two damaged tools of the same item can be repaired in the crafting window, which removes enchantments and then combines their remaining uses into a new item.

I have tested that, in vanilla 1.16.1, the given steps do give the expected result: a fully repaired diamond pickaxe. I have also tested the above steps in the given Forge version using diamond pickaxes enchanted with Efficiency 1, which also results in no crafting result.

Original bug report on forums (this is one part of the report)

Screenshot of result of given steps on given Forge version