I went onto the new beta and I threw on an elytra to see how the pancape cape would look with it and to my suprise the elytra just turned invisible. I tested to see if it was actually on and I could glide and everything. No resource packs have been applied other than the default.
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Thank you for your report!
We're actually already tracking this issue at MCPE-63117, so I will resolve and link 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.
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