How to disable ext4 feature for custom image?

[paulmenzel]

Buliding https://github.com/paulmenzel/ubuntu-bbb/, containing mkosi.extra/etc/repart.d/10-root.conf, with mkosi -d ubuntu -r jammy -t disk -o ubuntu-jammy --debug the feature orphan_file is enabled.

How do I do the same as below for my image?

mkosi/mkosi.conf.d/30-debian-ubuntu/mkosi.conf.d/20-ext4-orphan-file.conf

Lines 8 to 11 in 50d6e95

	[Content]
	# "orphan_file" is enabled by default in recent versions of mkfs.ext4 but not supported by the Jammy/Focal kernels
	# so we explicitly disable it.
	Environment=SYSTEMD_REPART_MKFS_OPTIONS_EXT4="-O ^orphan_file"