define interaction with clear-site-data

spec/index.bs

@@ -326,7 +326,7 @@ and "<dfn><code>signed-out</code></dfn>"
 
 The user agent checks all page and subresource loads for an HTTP response
 [=header=] named <dfn><code>IdP-SignIn-Status</code></dfn>, whose value is
-parsed as HTTP [[RFC9110#parameter|Parameter]]s.
+parsed as HTTP [[RFC9110#section-5.6.6|Parameter]]s.
 If that header exists and the first parameter has a name of `action`,
 the user agent must process it as follows:
 
@@ -383,6 +383,13 @@ Map=] with the [=map/key=] being  [=/this=]'s [=/relevant settings object=]'s
 [=environment settings object/origin=] and the value being [=signed-in=] (for
 `recordSignIn`) or [=signed-out=] (for `recordSignOut`).
 
+### Interaction with `Clear-Site-Data`
+
+When the user agent receives a <a http-header>Clear-Site-Data</a> header with a
+value of `"cookies"`, while [$clear cookies for origin|clearing cookies for
+origin$] it must remove any entries in the [=IDP Sign-in Status Map=] where the
+[=map/key=] is the input origin.
+
 <!-- ============================================================ -->
 ## The connected accounts set ## {#browser-connected-accounts-set}
 <!-- ============================================================ -->