If you place glass above an end portal, the portal block will start flickering and show the block below it. I did this on a beach and half the time I would see sand and half the time end portal block. I was trying to do a floor with end portal blocks covered in glass, but I canβt do that unless the bug is fixed. (Though I have not tried layering the end portals)
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Thank you for your report!
We're actually already tracking this issue at MCPE-55778, 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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