diff --git a/pc/media_session.cc b/pc/media_session.cc
index a118beebb0..f146562b37 100644
--- a/pc/media_session.cc
+++ b/pc/media_session.cc
@@ -1254,17 +1254,6 @@ void NegotiateRtpHeaderExtensions(const RtpHeaderExtensions& local_extensions,
                                   const RtpHeaderExtensions& offered_extensions,
                                   webrtc::RtpExtension::Filter filter,
                                   RtpHeaderExtensions* negotiated_extensions) {
-  // TransportSequenceNumberV2 is not offered by default. The special logic for
-  // the TransportSequenceNumber extensions works as follows:
-  // Offer       Answer
-  // V1          V1 if in local_extensions.
-  // V1 and V2   V2 regardless of local_extensions.
-  // V2          V2 regardless of local_extensions.
-  const webrtc::RtpExtension* transport_sequence_number_v2_offer =
-      FindHeaderExtensionByUriDiscardUnsupported(
-          offered_extensions,
-          webrtc::RtpExtension::kTransportSequenceNumberV2Uri, filter);
-
   bool frame_descriptor_in_local = false;
   bool dependency_descriptor_in_local = false;
   bool abs_capture_time_in_local = false;
@@ -1276,29 +1265,16 @@ void NegotiateRtpHeaderExtensions(const RtpHeaderExtensions& local_extensions,
       dependency_descriptor_in_local = true;
     else if (ours.uri == webrtc::RtpExtension::kAbsoluteCaptureTimeUri)
       abs_capture_time_in_local = true;
+
     const webrtc::RtpExtension* theirs =
         FindHeaderExtensionByUriDiscardUnsupported(offered_extensions, ours.uri,
                                                    filter);
     if (theirs) {
-      if (transport_sequence_number_v2_offer &&
-          ours.uri == webrtc::RtpExtension::kTransportSequenceNumberUri) {
-        // Don't respond to
-        // http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01
-        // if we get an offer including
-        // http://www.webrtc.org/experiments/rtp-hdrext/transport-wide-cc-02
-        continue;
-      } else {
-        // We respond with their RTP header extension id.
-        negotiated_extensions->push_back(*theirs);
-      }
+      // We respond with their RTP header extension id.
+      negotiated_extensions->push_back(*theirs);
     }
   }
 
-  if (transport_sequence_number_v2_offer) {
-    // Respond that we support kTransportSequenceNumberV2Uri.
-    negotiated_extensions->push_back(*transport_sequence_number_v2_offer);
-  }
-
   // Frame descriptors support. If the extension is not present locally, but is
   // in the offer, we add it to the list.
   if (!dependency_descriptor_in_local) {
diff --git a/pc/media_session_unittest.cc b/pc/media_session_unittest.cc
index f4fd09cba0..ecfb4397bb 100644
--- a/pc/media_session_unittest.cc
+++ b/pc/media_session_unittest.cc
@@ -1731,30 +1731,72 @@ TEST_F(MediaSessionDescriptionFactoryTest, TestOfferAnswerWithRtpExtensions) {
 }
 
 // Create a audio/video offer and answer and ensure that the
-// TransportSequenceNumber RTP header extensions are handled correctly. 02 is
-// supported and should take precedence even though not listed among locally
-// supported extensions.
+// TransportSequenceNumber RTP v1 and v2 header extensions are handled
+// correctly.
 TEST_F(MediaSessionDescriptionFactoryTest,
-       TestOfferAnswerWithTransportSequenceNumberInOffer) {
+       TestOfferAnswerWithTransportSequenceNumberV1LocalAndV1InOffer) {
   TestTransportSequenceNumberNegotiation(
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),   // Local.
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),   // Offer.
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01));  // Expected answer.
 }
 TEST_F(MediaSessionDescriptionFactoryTest,
-       TestOfferAnswerWithTransportSequenceNumber01And02InOffer) {
+       TestOfferAnswerWithTransportSequenceNumberV1LocalAndV1V2InOffer) {
   TestTransportSequenceNumberNegotiation(
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),       // Local.
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01And02),  // Offer.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01));  // Expected answer.
+}
+TEST_F(MediaSessionDescriptionFactoryTest,
+       TestOfferAnswerWithTransportSequenceNumberV1LocalAndV2InOffer) {
+  TestTransportSequenceNumberNegotiation(
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),  // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02),  // Offer.
+      {});                                                  // Expected answer.
+}
+TEST_F(MediaSessionDescriptionFactoryTest,
+       TestOfferAnswerWithTransportSequenceNumberV2LocalAndV1InOffer) {
+  TestTransportSequenceNumberNegotiation(
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02),  // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),  // Offer.
+      {});                                                  // Expected answer.
+}
+TEST_F(MediaSessionDescriptionFactoryTest,
+       TestOfferAnswerWithTransportSequenceNumberV2LocalAndV1V2InOffer) {
+  TestTransportSequenceNumberNegotiation(
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02),       // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01And02),  // Offer.
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02));  // Expected answer.
 }
 TEST_F(MediaSessionDescriptionFactoryTest,
-       TestOfferAnswerWithTransportSequenceNumber02InOffer) {
+       TestOfferAnswerWithTransportSequenceNumberV2LocalAndV2InOffer) {
   TestTransportSequenceNumberNegotiation(
-      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),   // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02),   // Local.
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02),   // Offer.
       MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02));  // Expected answer.
 }
+TEST_F(MediaSessionDescriptionFactoryTest,
+       TestOfferAnswerWithTransportSequenceNumberV1V2LocalAndV1InOffer) {
+  TestTransportSequenceNumberNegotiation(
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01And02),  // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01),       // Offer.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01));  // Expected answer.
+}
+TEST_F(MediaSessionDescriptionFactoryTest,
+       TestOfferAnswerWithTransportSequenceNumberV1V2LocalAndV2InOffer) {
+  TestTransportSequenceNumberNegotiation(
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01And02),  // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02),       // Offer.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber02));  // Expected answer.
+}
+TEST_F(MediaSessionDescriptionFactoryTest,
+       TestOfferAnswerWithTransportSequenceNumberV1V2LocalAndV1V2InOffer) {
+  TestTransportSequenceNumberNegotiation(
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01And02),  // Local.
+      MAKE_VECTOR(kRtpExtensionTransportSequenceNumber01And02),  // Offer.
+      MAKE_VECTOR(
+          kRtpExtensionTransportSequenceNumber01And02));  // Expected answer.
+}
 
 TEST_F(MediaSessionDescriptionFactoryTest,
        TestNegotiateFrameDescriptorWhenUnexposedLocally) {