Address @AngeloKai's comments

index.bs

@@ -691,8 +691,9 @@ When this method is invoked, the user agent MUST execute the following algorithm
     platform during the lifetime of |lifetimeTimer| and do the following:
 
     Issue: The definitions of "lifetime of" and "becomes available" are intended to represent how
-    devices are hotplugged into browsers, and are under-specified. Resolving this with good definitions
-    or some other means will be addressed by resolving [Issue #613](https://github.com/w3c/webauthn/issues/613).
+    devices are hotplugged into (USB) or discovered by (NFC) browsers, and are under-specified.
+    Resolving this with good definitions or some other means will be addressed by resolving
+    [Issue #613](https://github.com/w3c/webauthn/issues/613).
 
     1. If {{AuthenticatorSelectionCriteria/authenticatorAttachment}} is [=present|present=] and its value is not equal
         to |authenticator|'s attachment modality, [=iteration/continue=].
@@ -909,8 +910,9 @@ method is invoked, the user agent MUST:
     |lifetimeTimer|, perform the following steps:
 
     Issue: The definitions of "lifetime of" and "becomes available" are intended to represent how
-    devices are hotplugged into browsers, and are under-specified. Resolving this with good definitions
-    or some other means will be addressed by resolving [Issue #613](https://github.com/w3c/webauthn/issues/613).
+    devices are hotplugged into (USB) or discovered by (NFC) browsers, and are under-specified.
+    Resolving this with good definitions or some other means will be addressed by resolving
+    [Issue #613](https://github.com/w3c/webauthn/issues/613).
 
     1. Let |allowCredentialDescriptorList| be a new [=list=].