diff --git a/media/engine/webrtc_media_engine.cc b/media/engine/webrtc_media_engine.cc
index faba9b1d13..5ea99b6e41 100644
--- a/media/engine/webrtc_media_engine.cc
+++ b/media/engine/webrtc_media_engine.cc
@@ -18,6 +18,7 @@
 #include "api/video_codecs/video_decoder_factory.h"
 #include "api/video_codecs/video_encoder_factory.h"
 #include "media/engine/webrtc_voice_engine.h"
+#include "system_wrappers/include/field_trial.h"
 
 #ifdef HAVE_WEBRTC_VIDEO
 #include "media/engine/webrtc_video_engine.h"
@@ -67,6 +68,13 @@ std::unique_ptr<MediaEngineInterface> WebRtcMediaEngineFactory::Create(
 }
 
 namespace {
+// If this FieldTrial is enabled, we will not filter out the abs-send-time
+// header extension when the TWCC extensions were also negotiated, but keep
+// kAbsSendTimeUri also if kTransportSequenceNumberUri is present.
+bool IsKeepAbsSendTimeExtensionFieldTrialEnabled() {
+  return webrtc::field_trial::IsEnabled("WebRTC-KeepAbsSendTimeExtension");
+}
+
 // Remove mutually exclusive extensions with lower priority.
 void DiscardRedundantExtensions(
     std::vector<webrtc::RtpExtension>* extensions,
@@ -143,14 +151,20 @@ std::vector<webrtc::RtpExtension> FilterRtpExtensions(
         });
     result.erase(it, result.end());
 
-    // Keep just the highest priority extension of any in the following list.
-    static const char* const kBweExtensionPriorities[] = {
-        webrtc::RtpExtension::kTransportSequenceNumberUri,
-        webrtc::RtpExtension::kAbsSendTimeUri,
-        webrtc::RtpExtension::kTimestampOffsetUri};
-    DiscardRedundantExtensions(&result, kBweExtensionPriorities);
+    // Keep just the highest priority extension of any in the following lists.
+    if (IsKeepAbsSendTimeExtensionFieldTrialEnabled()) {
+      static const char* const kBweExtensionPriorities[] = {
+          webrtc::RtpExtension::kAbsSendTimeUri,
+          webrtc::RtpExtension::kTimestampOffsetUri};
+      DiscardRedundantExtensions(&result, kBweExtensionPriorities);
+    } else {
+      static const char* const kBweExtensionPriorities[] = {
+          webrtc::RtpExtension::kTransportSequenceNumberUri,
+          webrtc::RtpExtension::kAbsSendTimeUri,
+          webrtc::RtpExtension::kTimestampOffsetUri};
+      DiscardRedundantExtensions(&result, kBweExtensionPriorities);
+    }
   }
-
   return result;
 }
 
diff --git a/media/engine/webrtc_media_engine_unittest.cc b/media/engine/webrtc_media_engine_unittest.cc
index 0241607f90..19542a97c5 100644
--- a/media/engine/webrtc_media_engine_unittest.cc
+++ b/media/engine/webrtc_media_engine_unittest.cc
@@ -17,6 +17,7 @@
 #include "api/video_codecs/builtin_video_encoder_factory.h"
 #include "media/engine/webrtc_media_engine.h"
 #include "modules/audio_processing/include/audio_processing.h"
+#include "test/field_trial.h"
 #include "test/gtest.h"
 
 using webrtc::RtpExtension;
@@ -198,6 +199,25 @@ TEST(WebRtcMediaEngineTest, FilterRtpExtensions_RemoveRedundantBwe_1) {
   EXPECT_EQ(RtpExtension::kTransportSequenceNumberUri, filtered[0].uri);
 }
 
+TEST(WebRtcMediaEngineTest,
+     FilterRtpExtensions_RemoveRedundantBwe_1_KeepAbsSendTime) {
+  std::vector<RtpExtension> extensions;
+  webrtc::test::ScopedFieldTrials override_field_trials_(
+      "WebRTC-KeepAbsSendTimeExtension/Enabled/");
+  extensions.push_back(
+      RtpExtension(RtpExtension::kTransportSequenceNumberUri, 3));
+  extensions.push_back(RtpExtension(RtpExtension::kTimestampOffsetUri, 9));
+  extensions.push_back(RtpExtension(RtpExtension::kAbsSendTimeUri, 6));
+  extensions.push_back(
+      RtpExtension(RtpExtension::kTransportSequenceNumberUri, 1));
+  extensions.push_back(RtpExtension(RtpExtension::kTimestampOffsetUri, 14));
+  std::vector<webrtc::RtpExtension> filtered =
+      FilterRtpExtensions(extensions, SupportedExtensions2, true);
+  EXPECT_EQ(2u, filtered.size());
+  EXPECT_EQ(RtpExtension::kTransportSequenceNumberUri, filtered[0].uri);
+  EXPECT_EQ(RtpExtension::kAbsSendTimeUri, filtered[1].uri);
+}
+
 TEST(WebRtcMediaEngineTest, FilterRtpExtensions_RemoveRedundantBweEncrypted_1) {
   std::vector<RtpExtension> extensions;
   extensions.push_back(
@@ -219,6 +239,31 @@ TEST(WebRtcMediaEngineTest, FilterRtpExtensions_RemoveRedundantBweEncrypted_1) {
   EXPECT_NE(filtered[0].encrypt, filtered[1].encrypt);
 }
 
+TEST(WebRtcMediaEngineTest,
+     FilterRtpExtensions_RemoveRedundantBweEncrypted_1_KeepAbsSendTime) {
+  std::vector<RtpExtension> extensions;
+  webrtc::test::ScopedFieldTrials override_field_trials_(
+      "WebRTC-KeepAbsSendTimeExtension/Enabled/");
+  extensions.push_back(
+      RtpExtension(RtpExtension::kTransportSequenceNumberUri, 3));
+  extensions.push_back(
+      RtpExtension(RtpExtension::kTransportSequenceNumberUri, 4, true));
+  extensions.push_back(RtpExtension(RtpExtension::kTimestampOffsetUri, 9));
+  extensions.push_back(RtpExtension(RtpExtension::kAbsSendTimeUri, 6));
+  extensions.push_back(
+      RtpExtension(RtpExtension::kTransportSequenceNumberUri, 1));
+  extensions.push_back(
+      RtpExtension(RtpExtension::kTransportSequenceNumberUri, 2, true));
+  extensions.push_back(RtpExtension(RtpExtension::kTimestampOffsetUri, 14));
+  std::vector<webrtc::RtpExtension> filtered =
+      FilterRtpExtensions(extensions, SupportedExtensions2, true);
+  EXPECT_EQ(3u, filtered.size());
+  EXPECT_EQ(RtpExtension::kTransportSequenceNumberUri, filtered[0].uri);
+  EXPECT_EQ(RtpExtension::kTransportSequenceNumberUri, filtered[1].uri);
+  EXPECT_EQ(RtpExtension::kAbsSendTimeUri, filtered[2].uri);
+  EXPECT_NE(filtered[0].encrypt, filtered[1].encrypt);
+}
+
 TEST(WebRtcMediaEngineTest, FilterRtpExtensions_RemoveRedundantBwe_2) {
   std::vector<RtpExtension> extensions;
   extensions.push_back(RtpExtension(RtpExtension::kTimestampOffsetUri, 1));