It´s a really good mod! However I started a world on 1.20.5 and got to the point of upgrading to enderite and when I put the three items on the smithing table the game crashes under the error "The game crashed whilst container click Error: java.lang.UnsupportedOperationException". I tried checking if it was incompatible with some other mod but even being the only mod the crash still happens.

Edit: It also seems I can't combine enderite armor with the elytra

The reason was, that the ItemEnchantments returns an Unmodifiable Map, that I want to modify.
But now I have fixed that.

Yes, the Enderite Elytra is not Craftable.
And I have also now fixed it.

The Problem is, that Minecraft has changed a lot in their code.

In the next update, everything is fixed.

If the Item have an enchantment, then it still crashes.
But now I have fixed it and made it smarter.
If you have for example Unbreaking 2 on your Chestplate and Elytra, then you get Unbreaking 3 on your Elytra Chestplate

It fully works now, thank you!!