Safari does not fire pageswap event for cross-origin navigations (#28987)

* Safari does not fire `pageswap` event for cross-origin navigations

Fixes #28973

* Update api/Window.json

Co-authored-by: Daniel D. Beck <daniel@ddbeck.com>

---------

Co-authored-by: Daniel D. Beck <daniel@ddbeck.com>

Author: caugner

api/Window.json

@@ -4345,7 +4345,9 @@
             "opera": "mirror",
             "opera_android": "mirror",
             "safari": {
-              "version_added": "18.2"
+              "version_added": "18.2",
+              "partial_implementation": true,
+              "notes": "Cross-origin navigation does not fire `pageswap`. See [bug 306447](https://webkit.org/b/306447)."
             },
             "safari_ios": "mirror",
             "samsunginternet_android": "mirror",