2025-03-31, 03:40 AM
Huzzah it's working now! Thank you TheDreadPirate for giving your time to help me out. The subvol / subvolid was the missing piece.
New line in /etc/fstab is:
/dev/nvme0n1p4 /media/Data btrfs defaults,subvolid=5 0 2
New line in /etc/fstab is:
/dev/nvme0n1p4 /media/Data btrfs defaults,subvolid=5 0 2