diff --git a/sphinx/builders/linkcheck.py b/sphinx/builders/linkcheck.py
index bc4b22042..a81a0253d 100644
--- a/sphinx/builders/linkcheck.py
+++ b/sphinx/builders/linkcheck.py
@@ -460,11 +460,8 @@ class HyperlinkAvailabilityCheckWorker(Thread):
                                                  config=self.config, auth=auth_info,
                                                  **kwargs)
                         response.raise_for_status()
-                    # When there is a ConnectionError from the HEAD request, it might be due to
-                    # the webserver intentionally dropping the connection when it sees HEAD requests
-                    # but still responding properly to GET requests. This has been observed in the
-                    # wild with at https://patft.uspto.gov/.
-                    # See https://github.com/sphinx-doc/sphinx/issues/9306 for more details.
+                    # Servers drop the connection on HEAD requests, causing
+                    # ConnectionError.
                     except (ConnectionError, HTTPError, TooManyRedirects) as err:
                         if isinstance(err, HTTPError) and err.response.status_code == 429:
                             raise