Hello

> "No device found"
> That's plugged into the USB port on which I regularly back up on USB sticks,
> and uses the camera's cable which worked fine with the previous Devuan.

Is the camera recognized as a USB device?

lsusb

Is the kernel module loaded?

lsmod | grep uvc

modprobe uvcvideo

Any related error in dmesg?

dmesg

Best regards,