diff --git a/docshell/base/nsDocShell.cpp b/docshell/base/nsDocShell.cpp
index 0a8a5b3e2905..fd625d7ec892 100644
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -2823,29 +2823,6 @@ nsDocShell::GetSameTypeRootTreeItemIgnoreBrowserBoundaries(
   return NS_OK;
 }
 
-/* static */
-bool nsDocShell::CanAccessItem(nsIDocShellTreeItem* aTargetItem,
-                               nsIDocShellTreeItem* aAccessingItem,
-                               bool aConsiderOpener) {
-  MOZ_ASSERT(aTargetItem, "Must have target item!");
-
-  if (!aAccessingItem) {
-    // Good to go
-    return true;
-  }
-
-  nsCOMPtr<nsIDocShell> targetDS = do_QueryInterface(aTargetItem);
-  nsCOMPtr<nsIDocShell> accessingDS = do_QueryInterface(aAccessingItem);
-  if (!targetDS || !accessingDS) {
-    // We must be able to convert both to nsIDocShell.
-    return false;
-  }
-
-  return Cast(accessingDS)
-      ->mBrowsingContext->CanAccess(Cast(targetDS)->mBrowsingContext,
-                                    aConsiderOpener);
-}
-
 void nsDocShell::AssertOriginAttributesMatchPrivateBrowsing() {
   // Chrome docshells must not have a private browsing OriginAttribute
   // Content docshells must maintain the equality:
diff --git a/docshell/base/nsDocShell.h b/docshell/base/nsDocShell.h
index 422a94c3f6f0..0223416f7b20 100644
--- a/docshell/base/nsDocShell.h
+++ b/docshell/base/nsDocShell.h
@@ -539,11 +539,8 @@ class nsDocShell final : public nsDocLoader,
   nsDocShell(mozilla::dom::BrowsingContext* aBrowsingContext,
              uint64_t aContentWindowID);
 
-  // Security checks to prevent frameset spoofing. See comments at
-  // implementation sites.
-  static bool CanAccessItem(nsIDocShellTreeItem* aTargetItem,
-                            nsIDocShellTreeItem* aAccessingItem,
-                            bool aConsiderOpener = true);
+  // Security check to prevent frameset spoofing. See comments at
+  // implementation site.
   static bool ValidateOrigin(nsIDocShellTreeItem* aOriginTreeItem,
                              nsIDocShellTreeItem* aTargetTreeItem);