Recently built a new computer, didn't want to deal with the headaches of distros like Gentoo like I did at work back in the mid 2000's, so I went with Mint. Had to manually install mdadm in the live CD environment, used mdadm to create RAID1 mirror for /var, /tmp and /home on a magnetic drive so I didn't wear out my NVMe drive with heavy writing (SWAP, /var, /tmp and /home are the parts of the linux filesystem that receive the most write traffic - learned this back in the day).

Anyway, the installer couldn't understand that since I used mdadm to create the RAID array, that the volume blk_id for the three RAID devices should be written to /etc/fstab for their appropriate mount points before the first boot of the system - and instead used the partitions on the first disk. Wonderful. So let's create a RAID then. Nope. Get fucked, user.

Had to end up installing with SWAP on the first two partitions of both magnetic drives (have 64GB of SWAP, lol) and /var, /tmp and /home on the NVMe drive, rebooted, and manually moved over /var, /tmp and /home to the first magnetic drive, used mdadm to create the RAID mirror, manually added blk_id of the mdX devices to /etc/fstab mount points, and rebooted. Worked perfectly after that.

Hey distro mods - INCLUDE mdadm on your install disk and take into account if someone fucking creates a mirror during install instead of having people manually do this on the first boot - fucking their shit.

THIS, along with other issues, is what stops linux from dominating the normiesphere.

The off-side to that is having to find a fix for your problem from another version of linux from the 80's on some backup of a message board after a week of searching.