Actually the installation guide for arch asks you to use `genfstab -U /mnt >> /mnt/etc/fstab` which basically copies over whatever was mounted at the live envir

Actually the installation guide for arch asks you to use `genfstab -U /mnt >> /mnt/etc/fstab` which basically copies over whatever was mounted at the live environment (taking off the /mnt), I'm pretty sure tmpfs for /tmp was there by default last time I installed.