diff --git a/netwerk/protocol/http/nsCORSListenerProxy.cpp b/netwerk/protocol/http/nsCORSListenerProxy.cpp
index b1054891e562..ab210f1fbde6 100644
--- a/netwerk/protocol/http/nsCORSListenerProxy.cpp
+++ b/netwerk/protocol/http/nsCORSListenerProxy.cpp
@@ -1290,13 +1290,13 @@ nsCORSListenerProxy::RemoveFromCorsPreflightCache(nsIURI* aURI,
 }
 
 nsresult
-NS_StartCORSPreflight(nsIChannel* aRequestChannel,
-                      nsIStreamListener* aListener,
-                      nsIPrincipal* aPrincipal,
-                      nsICorsPreflightCallback* aCallback,
-                      bool aWithCredentials,
-                      nsTArray<nsCString>& aUnsafeHeaders,
-                      nsIChannel** aPreflightChannel)
+nsCORSListenerProxy::StartCORSPreflight(nsIChannel* aRequestChannel,
+                                        nsIStreamListener* aListener,
+                                        nsIPrincipal* aPrincipal,
+                                        nsICorsPreflightCallback* aCallback,
+                                        bool aWithCredentials,
+                                        nsTArray<nsCString>& aUnsafeHeaders,
+                                        nsIChannel** aPreflightChannel)
 {
   *aPreflightChannel = nullptr;
 
diff --git a/netwerk/protocol/http/nsCORSListenerProxy.h b/netwerk/protocol/http/nsCORSListenerProxy.h
index 947d3e7a8ad6..246cd27e7b20 100644
--- a/netwerk/protocol/http/nsCORSListenerProxy.h
+++ b/netwerk/protocol/http/nsCORSListenerProxy.h
@@ -24,18 +24,10 @@ class nsIPrincipal;
 class nsINetworkInterceptController;
 class nsICorsPreflightCallback;
 
-nsresult
-NS_StartCORSPreflight(nsIChannel* aRequestChannel,
-                      nsIStreamListener* aListener,
-                      nsIPrincipal* aPrincipal,
-                      nsICorsPreflightCallback* aCallback,
-                      bool aWithCredentials,
-                      nsTArray<nsCString>& aACUnsafeHeaders,
-                      nsIChannel** aPreflightChannel);
-
 namespace mozilla {
 namespace net {
 class HttpChannelParent;
+class nsHttpChannel;
 }
 }
 
@@ -55,11 +47,6 @@ public:
   nsCORSListenerProxy(nsIStreamListener* aOuter,
                       nsIPrincipal* aRequestingPrincipal,
                       bool aWithCredentials);
-  nsCORSListenerProxy(nsIStreamListener* aOuter,
-                      nsIPrincipal* aRequestingPrincipal,
-                      bool aWithCredentials,
-                      const nsCString& aPreflightMethod,
-                      const nsTArray<nsCString>& aPreflightHeaders);
 
   NS_DECL_ISUPPORTS
   NS_DECL_NSIREQUESTOBSERVER
@@ -81,10 +68,26 @@ public:
 private:
   // Only HttpChannelParent can call RemoveFromCorsPreflightCache
   friend class mozilla::net::HttpChannelParent;
+  // Only nsHttpChannel can invoke CORS preflights
+  friend class mozilla::net::nsHttpChannel;
 
   static void RemoveFromCorsPreflightCache(nsIURI* aURI,
                                            nsIPrincipal* aRequestingPrincipal);
 
+  nsCORSListenerProxy(nsIStreamListener* aOuter,
+                      nsIPrincipal* aRequestingPrincipal,
+                      bool aWithCredentials,
+                      const nsCString& aPreflightMethod,
+                      const nsTArray<nsCString>& aPreflightHeaders);
+
+  static nsresult StartCORSPreflight(nsIChannel* aRequestChannel,
+                                     nsIStreamListener* aListener,
+                                     nsIPrincipal* aPrincipal,
+                                     nsICorsPreflightCallback* aCallback,
+                                     bool aWithCredentials,
+                                     nsTArray<nsCString>& aACUnsafeHeaders,
+                                     nsIChannel** aPreflightChannel);
+
   ~nsCORSListenerProxy();
 
   nsresult UpdateChannel(nsIChannel* aChannel, DataURIHandling aAllowDataURI);
diff --git a/netwerk/protocol/http/nsHttpChannel.cpp b/netwerk/protocol/http/nsHttpChannel.cpp
index 8019da29438a..fca4f62a9b65 100644
--- a/netwerk/protocol/http/nsHttpChannel.cpp
+++ b/netwerk/protocol/http/nsHttpChannel.cpp
@@ -453,10 +453,12 @@ nsHttpChannel::ContinueConnect()
     if (!mIsCorsPreflightDone && mRequireCORSPreflight &&
         mInterceptCache != INTERCEPTED) {
         nsCOMPtr<nsIChannel> preflightChannel;
-        nsresult rv = NS_StartCORSPreflight(this, mListener,
-                                            mPreflightPrincipal, this,
-                                            mWithCredentials, mUnsafeHeaders,
-                                            getter_AddRefs(preflightChannel));
+        nsresult rv =
+            nsCORSListenerProxy::StartCORSPreflight(this, mListener,
+                                                    mPreflightPrincipal, this,
+                                                    mWithCredentials,
+                                                    mUnsafeHeaders,
+                                                    getter_AddRefs(preflightChannel));
         return rv;
     }