It worked fine using nitropy nk3 update, so it probably was/is a bug in the NitroKey App:
PS C:\Users\foo> nitropy nk3 update
Command line tool to interact with Nitrokey devices 0.11.4
Do you want to download the firmware version v1.8.3? [Y/n]:
Download v1.8.3: 100%|β¦| 1.04M/1.04M [00:00<00:00, 5.22MB/s]
Current firmware version: v1.8.2
Updated firmware version: v1.8.3
Please do not remove the device or insert any other Nitrokey devices during the update. Doing so may damage the device.
Do you want to perform the firmware update now? [y/N]: y
Please press the touch button to reboot the device into bootloader mode β¦
Perform firmware update: 100%|β¦| 525k/525k [00:05<00:00, 89.5kB/s]
Finalize upgrade: 100%|β¦| 100/100 [00:02<00:00, 44.95%/s]
Firmware version: v1.8.3
Init status: ok
Free blocks (int): 4
Free blocks (ext): 465
Variant: LPC55
PS C:\Users\foo>
Maybe 0.5.0rc1 was referring to an old pre-release version of the piv-authenticator Trussed app β¦?
nitropy nk3 update
Command line tool to interact with Nitrokey devices 0.11.4
Do you want to download the firmware version v1.8.3? [Y/n]: y
Download v1.8.3: 100%|βββββββββββββββββββββ| 1.04M/1.04M [00:00<00:00, 2.03MB/s]
Current firmware version: v1.8.2
Updated firmware version: v1.8.3
Please do not remove the device or insert any other Nitrokey devices during the update. Doing so may damage the device.
Do you want to perform the firmware update now? [y/N]: y
Please press the touch button to reboot the device into bootloader mode β¦
Critical error:
An unhandled exception occurred
Exception encountered: SPSDKConnectionError()
Critical error occurred, exiting now
Unexpected? Is this a bug? Would you like to get support/help?