./install from Linux Mint 20.2 fails

[pdinoto]

Version (k3OS / kernel)
v0.20.11-k3s2r1

Architecture
amd64

Describe the bug
install.sh on a bare metal install can't mount the HFS partition, making install fail.

To Reproduce
Launch a Linux Mint 20.2 live installer USB disk
Download install script and execute
Execute ./install.sh /dev/nvme0n1 https://github.com/rancher/k3os/releases/download/v0.22.2-k3s2r0/k3os-amd64.iso

or use --takeover and use the already downloaded ISO from previous attempt:
./install.sh --takeover /dev/nvme0n1 https://github.com/rancher/k3os/releases/download/v0.22.2-k3s2r0/k3os-amd64.iso

Expected behavior
A working K3OS system is installed on the only available disk on the system

Actual behavior
On the terse attempt, the installer fails silently.
On the K3S_DEBUG=true attempt the installer fails with

+ mkfs.vfat -F 32 /dev/nvme0n1p1
mkfs.fat 4.1 (2017-01-24)
+ fatlabel /dev/nvme0n1p1 K3OS_GRUB
+ do_mount
+ TARGET=/run/k3os/target
+ mkdir -p /run/k3os/target
+ mount /dev/nvme0n1p2 /run/k3os/target
+ mkdir -p /run/k3os/target/boot
+ '[' -n /dev/nvme0n1p1 ']'
+ mkdir -p /run/k3os/target/boot/efi
+ mount /dev/nvme0n1p1 /run/k3os/target/boot/efi
+ mkdir -p /run/k3os/iso
+ mount -o ro /dev/loop1p3 /run/k3os/iso
mount: /run/k3os/iso: wrong fs type, bad option, bad superblock on /dev/loop1p3, missing codepage or helper program, or other error.

Additional context
Attempts to mount the 3rd partition on the loop-mounted ISO image fails with

[  995.633316] hfsplus: invalid secondary volume header
[  995.633317] hfsplus: unable to find HFS+ superblock
[ 1177.731774] hfsplus: invalid secondary volume header
[ 1177.731777] hfsplus: unable to find HFS+ superblock

ISO images were checksum checked.

[pdinoto]

Complete transcript of the install attempt.

[pdinoto]

Latest available version at this time v0.22.2-k3s2r0, installs fine.