If you have created a new APFS volume on a Mac for some purpose, perhaps to run a different version of MacOS on, you may eventually wish to remove that volume from the APFS container.
Deleting an APFS volume removes all data on that volume and is irreversible, so make sure that you are targeting the proper volume to delete, and be sure you have sufficient backups of any data you want to preserve.
How to Delete APFS Volume from Container on Mac
Be certain you have a complete backup of the Mac made before modifying any volumes or containers in Disk Utility.
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