If you put items in a shulker box (that's been placed). Then if you leave the game all of those items that were put in the shulker box aren't there anymore. Any shulker boxes that have not been placed in the world before you leave the game are not affected.
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Asteraoth
Thank you for your report!
However, this issue is a Duplicate of MC-138938.
If you have additional information, please add it to that report.
Please search before reporting, as it's likely that one exists already.
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