&gt; And if I&#x27;m reading the linked GitHub issue correctly, this is about a specific plugin that runs in a sandbox on the YubiKey NEO, where the main codebase of the NEO is still proprietary?<p>No, it&#x27;s the code for the new YubiKey 4, which has been closed off.<p>&gt; What guarantee do you have that the code on the device matches the code on GitHub<p>Ideally, you can build and flash the firmware yourself.