Not very amusing story someone might nevertheless find quite funny:

I used to run RAID1 system with two RAID devices, one for 'system' and
one for 'data', with half of the array residing on an internal NVME
device and the other on an USB disk. I recently bought a webcam. When I
initially plugged that into an USB port, nothing happened. I then tried
a reboot. This caused the camera to appear (no idea if it also works)
but additionally, convinced something in the initramfs to remove all the
partitions on the USB disk from the corresponding RAID devices, thus
leaving me with two degraded arrays.

I'll now try to figure out how I can get my missing partitions back ...