When killed by Shulker (spawned in the overworld) and respawning, the Shulker turns invisible. The Shulker shoots proyectiles while invisible. When waking where the Shulker is supposed to be, it acts like a phantom block. The Shulker reapears when reloging.
Thank you for your report.
However, your ticket has been resolved as a duplicate.
This issue has been linked to the original bugreport: MC-68403. You can find or add further information on that report.
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