Versions:

• Curious Elytra: curiouselytra-forge-1.16.5-4.0.2.3.jar
• Caelus: caelus-forge-1.16.5-2.1.3.1.jar
• Curios: curios-forge-1.16.5-4.0.5.3.jar
• Forge: 36.2.6

Observed Behavior: Enchantments added by mods not functioning whilst Elytra is equipped in the Back Slot added by Curios API.

Expected Behavior: Enchantments added by mods should function the same as when Elytra is equipped in the Chest slot.

Steps to Reproduce:

1. Have an Elytra enchanted with modded enchantments.
   A. I have noticed it when attempting to use Winging from the More Enchantments mod. Winging is meant to deploy the Elytra automatically when falling. Reparation (from the same mod) also does not function as intended.
   B. Link to aforementioned mod: https://www.curseforge.com/minecraft/mc-mods/more-enchantments
2. Attempt to have enchantments work.
3. See that enchantments, in fact, do not work

Crash Log: No crashes, only failure to activate enchants.

This is much more easily done on the side of the mod implementing the enchantments. For example, More Enchantments can add integration to check for the curios slot in addition to the armor slot when applying their behavior. Whereas to get that same integration on my end, I would need to replicate their entire enchantment logic. And I would have to do this for every mod that adds an elytra enchantment. It's just much more work, and may not even be feasible depending on how the particular enchantments are coded.

So I'd suggest making this integration request to the enchantment developers.

Edit: I should mention that labeling this as a "bug" is a bit of a misnomer, as it's expected that enchantments do not work automatically with curios. This is more aptly a feature request for the implementing mod to include optional curios slot checks in their enchantment logic.