The attestation of the authenticator (the device which creates the passkey). In this case, the "device" is the password manager, so KeePassXC. This means that it's not detectable that a passkey was created and stored in KeePassXC, see also here
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Attestation of what specifically?
The attestation of the authenticator (the device which creates the passkey). In this case, the "device" is the password manager, so KeePassXC. This means that it's not detectable that a passkey was created and stored in KeePassXC, see also here