The wings of the enderdragon render one wing brighter(fullbright) and the other as if in shadow. (assuming new rendering engine brought this about)
+PS if using a texture pack with the 2nd wing layer (Top AND Bottom sides) game will still render both sides, but will appear rather glitchy
[attached image is custom texture pack, no other changes, fixed my texture that had both sides of the wing membrane already]
Thank you for your report!
We're actually already tracking this issue in MC-163353, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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