--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -1451,20 +1451,16 @@ pref("network.http.accept.default", "tex
 pref("network.http.sendRefererHeader",      2);
 // false=real referer, true=spoof referer (use target URI as referer)
 pref("network.http.referer.spoofSource", false);
 // 0=full URI, 1=scheme+host+port+path, 2=scheme+host+port
 pref("network.http.referer.trimmingPolicy", 0);
 // 0=always send, 1=send iff base domains match, 2=send iff hosts match
 pref("network.http.referer.XOriginPolicy", 0);
 
-// Controls whether we send HTTPS referres to other HTTPS sites.
-// By default this is enabled for compatibility (see bug 141641)
-pref("network.http.sendSecureXSiteReferrer", true);
-
 // Controls whether referrer attributes in <a>, <img>, <area>, <iframe>, and <link> are honoured
 pref("network.http.enablePerElementReferrer", true);
 
 // Maximum number of consecutive redirects before aborting.
 pref("network.http.redirection-limit", 20);
 
 // Enable http compression: comment this out in case of problems with 1.1
 // NOTE: support for "compress" has been disabled per bug 196406.

--- a/netwerk/protocol/http/HttpBaseChannel.cpp
+++ b/netwerk/protocol/http/HttpBaseChannel.cpp
@@ -1403,32 +1403,16 @@ HttpBaseChannel::SetReferrerWithPolicy(n
     // It's ok to send referrer for https-to-http scenarios if the referrer
     // policy is "unsafe-url", "origin", or "origin-when-cross-origin".
     if (referrerPolicy != REFERRER_POLICY_UNSAFE_URL &&
 	referrerPolicy != REFERRER_POLICY_ORIGIN_WHEN_XORIGIN &&
         referrerPolicy != REFERRER_POLICY_ORIGIN) {
 
       // in other referrer policies, https->http is not allowed...
       if (!match) return NS_OK;
-
-      // ...and https->https is possibly only allowed if the hosts match.
-      if (!gHttpHandler->SendSecureXSiteReferrer()) {
-        nsAutoCString referrerHost;
-        nsAutoCString host;
-
-        rv = referrer->GetAsciiHost(referrerHost);
-        if (NS_FAILED(rv)) return rv;
-
-        rv = mURI->GetAsciiHost(host);
-        if (NS_FAILED(rv)) return rv;
-
-        // GetAsciiHost returns lowercase hostname.
-        if (!referrerHost.Equals(host))
-          return NS_OK;
-      }
     }
   }
 
   // for cross-origin-based referrer changes (not just host-based), figure out
   // if the referrer is being sent cross-origin.
   nsCOMPtr<nsIURI> triggeringURI;
   bool isCrossOrigin = true;
   if (mLoadInfo) {

--- a/netwerk/protocol/http/nsHttpHandler.cpp
+++ b/netwerk/protocol/http/nsHttpHandler.cpp
@@ -197,17 +197,16 @@ nsHttpHandler::nsHttpHandler()
     , mLastUniqueID(NowInSeconds())
     , mSessionStartTime(0)
     , mLegacyAppName("Mozilla")
     , mLegacyAppVersion("5.0")
     , mProduct("Gecko")
     , mCompatFirefoxEnabled(false)
     , mUserAgentIsDirty(true)
     , mPromptTempRedirect(true)
-    , mSendSecureXSiteReferrer(true)
     , mEnablePersistentHttpsCaching(false)
     , mDoNotTrackEnabled(false)
     , mSafeHintEnabled(false)
     , mParentalControlEnabled(false)
     , mHandlerActive(false)
     , mTelemetryEnabled(false)
     , mAllowExperiments(true)
     , mDebugObservations(false)
@@ -1225,22 +1224,16 @@ nsHttpHandler::PrefsChanged(nsIPrefBranc
     }
 
     if (PREF_CHANGED(HTTP_PREF("qos"))) {
         rv = prefs->GetIntPref(HTTP_PREF("qos"), &val);
         if (NS_SUCCEEDED(rv))
             mQoSBits = (uint8_t) clamped(val, 0, 0xff);
     }
 
-    if (PREF_CHANGED(HTTP_PREF("sendSecureXSiteReferrer"))) {
-        rv = prefs->GetBoolPref(HTTP_PREF("sendSecureXSiteReferrer"), &cVar);
-        if (NS_SUCCEEDED(rv))
-            mSendSecureXSiteReferrer = cVar;
-    }
-
     if (PREF_CHANGED(HTTP_PREF("accept.default"))) {
         nsXPIDLCString accept;
         rv = prefs->GetCharPref(HTTP_PREF("accept.default"),
                                   getter_Copies(accept));
         if (NS_SUCCEEDED(rv))
             SetAccept(accept);
     }
 

--- a/netwerk/protocol/http/nsHttpHandler.h
+++ b/netwerk/protocol/http/nsHttpHandler.h
@@ -78,17 +78,16 @@ public:
     const nsAFlatCString &UserAgent();
 
     nsHttpVersion  HttpVersion()             { return mHttpVersion; }
     nsHttpVersion  ProxyHttpVersion()        { return mProxyHttpVersion; }
     uint8_t        ReferrerLevel()           { return mReferrerLevel; }
     bool           SpoofReferrerSource()     { return mSpoofReferrerSource; }
     uint8_t        ReferrerTrimmingPolicy()  { return mReferrerTrimmingPolicy; }
     uint8_t        ReferrerXOriginPolicy()   { return mReferrerXOriginPolicy; }
-    bool           SendSecureXSiteReferrer() { return mSendSecureXSiteReferrer; }
     bool           PackagedAppsEnabled()     { return mPackagedAppsEnabled; }
     uint8_t        RedirectionLimit()        { return mRedirectionLimit; }
     PRIntervalTime IdleTimeout()             { return mIdleTimeout; }
     PRIntervalTime SpdyTimeout()             { return mSpdyTimeout; }
     PRIntervalTime ResponseTimeout() {
       return mResponseTimeoutEnabled ? mResponseTimeout : 0;
     }
     PRIntervalTime ResponseTimeoutEnabled()  { return mResponseTimeoutEnabled; }
@@ -487,19 +486,16 @@ private:
     nsCString      mDeviceModelId;
 
     nsCString      mUserAgent;
     nsXPIDLCString mUserAgentOverride;
     bool           mUserAgentIsDirty; // true if mUserAgent should be rebuilt
 
 
     bool           mPromptTempRedirect;
-    // mSendSecureXSiteReferrer: default is false,
-    // if true allow referrer headers between secure non-matching hosts
-    bool           mSendSecureXSiteReferrer;
 
     // Persistent HTTPS caching flag
     bool           mEnablePersistentHttpsCaching;
 
     // For broadcasting tracking preference
     bool           mDoNotTrackEnabled;
 
     // for broadcasting safe hint;