I'm not sure if this is intentional or not, but you can add Protection IV to Elytra's via anvil. I edited the Minecraft wiki to say Protection is applicable through an anvil and the editors removed the edit and said you cannot on Java Edition.
Linked issues
Attachments
Comments
Arisa Bot
Thank you for your report!
We're tracking this issue as MC-95555, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – ✍️ Feedback and Suggestions – 📖 Game Wiki
-- I am a bot. This action was performed automagically! Please report any issues in Discord or Reddit
You can put any enchantment on just about anything in creative mode.
Try again in survival