The install script is still there, you don't have to use the ISO [0]. I prefer to do my own btrfs subvolumes, partitioning, tweaks, etc and just run the script after a base install. Uninstalling anything is a matter of seconds from the provided menus.

[0] https://learn.omacom.io/2/the-omarchy-manual/96/manual-insta...

I was curious, and i wasn't able to run an earlier version of the install script into a system i'd already set up; script complained about non-encrypted volumes. That was enough for me to walk away.

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