Recently we got access to the end and now have an ample supply of shulker boxes. However we discovered that when you open a upwards facing shulker box while standing on it, or stand on an open upwards facing shulker box, it crashes everyone else on the realm. I've seen that this was a problem in 1.13 beta, but apparently now it's back.
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Thank you for your report!
We're actually already tracking this issue at MCPE-60856, so I will resolve and link this ticket as a duplicate.
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