In the last few updates, having shulker boxes in player inventory will cause game to lag when inventory is opened. New patch 1.10.0 makes game hard freeze for a few seconds when inventory is opened. When the shulkers are removed from inventory there is still a minor delay, but when shulker boxes are added back, delay resumes. Attaching video of gameplay. Win 10 Pro 64 bit. Realms server.
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Thank you for your report!
We're actually already tracking this issue at MCPE-27167, so we will resolve and link this ticket as a duplicate.
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