Some months ago, I performed a web application penetration test on an application that used passkey for authentication. As part of the assessment, I also tested the passkey implementation and noticed some unusual behavior. During the debugging process, I created two short JavaScript helper functions that can be used to hook the browser APIs involved in passkey operations, allowing the passkey configuration to be inspected and manipulated. This gave me the ability to reliably perform some passkey tests and assess the configuration and implementation.