diff --git a/api/video/video_bitrate_allocator.cc b/api/video/video_bitrate_allocator.cc
index 8ad5f75..f4e843b 100644
--- a/api/video/video_bitrate_allocator.cc
+++ b/api/video/video_bitrate_allocator.cc
@@ -49,4 +49,6 @@
   return GetAllocation(parameters.total_bitrate.bps(), parameters.framerate);
 }
 
+void VideoBitrateAllocator::SetLegacyConferenceMode(bool enabled) {}
+
 }  // namespace webrtc
diff --git a/api/video/video_bitrate_allocator.h b/api/video/video_bitrate_allocator.h
index 04de04c..fdc86db 100644
--- a/api/video/video_bitrate_allocator.h
+++ b/api/video/video_bitrate_allocator.h
@@ -40,6 +40,10 @@
 
   virtual VideoBitrateAllocation Allocate(
       VideoBitrateAllocationParameters parameters);
+
+  // Deprecated: Only used to work around issues with the legacy conference
+  // screenshare mode and shouldn't be needed by any subclasses.
+  virtual void SetLegacyConferenceMode(bool enabled);
 };
 
 class VideoBitrateAllocationObserver {
diff --git a/api/video_codecs/video_codec.cc b/api/video_codecs/video_codec.cc
index d03082b..65c7243 100644
--- a/api/video_codecs/video_codec.cc
+++ b/api/video_codecs/video_codec.cc
@@ -83,6 +83,7 @@
       mode(VideoCodecMode::kRealtimeVideo),
       expect_encode_from_texture(false),
       timing_frame_thresholds({0, 0}),
+      legacy_conference_mode(false),
       codec_specific_() {}
 
 VideoCodecVP8* VideoCodec::VP8() {
diff --git a/api/video_codecs/video_codec.h b/api/video_codecs/video_codec.h
index c07fae9..dd3d344 100644
--- a/api/video_codecs/video_codec.h
+++ b/api/video_codecs/video_codec.h
@@ -146,6 +146,9 @@
     uint16_t outlier_ratio_percent;
   } timing_frame_thresholds;
 
+  // Legacy Google conference mode flag for simulcast screenshare
+  bool legacy_conference_mode;
+
   bool operator==(const VideoCodec& other) const = delete;
   bool operator!=(const VideoCodec& other) const = delete;
 
diff --git a/api/video_codecs/video_encoder_config.cc b/api/video_codecs/video_encoder_config.cc
index 6efcbf2..19b0135 100644
--- a/api/video_codecs/video_encoder_config.cc
+++ b/api/video_codecs/video_encoder_config.cc
@@ -55,7 +55,8 @@
       min_transmit_bitrate_bps(0),
       max_bitrate_bps(0),
       bitrate_priority(1.0),
-      number_of_streams(0) {}
+      number_of_streams(0),
+      legacy_conference_mode(false) {}
 
 VideoEncoderConfig::VideoEncoderConfig(VideoEncoderConfig&&) = default;
 
diff --git a/api/video_codecs/video_encoder_config.h b/api/video_codecs/video_encoder_config.h
index ef8db10..7a59dac 100644
--- a/api/video_codecs/video_encoder_config.h
+++ b/api/video_codecs/video_encoder_config.h
@@ -176,6 +176,9 @@
   // Max number of encoded VideoStreams to produce.
   size_t number_of_streams;
 
+  // Legacy Google conference mode flag for simulcast screenshare
+  bool legacy_conference_mode;
+
  private:
   // Access to the copy constructor is private to force use of the Copy()
   // method for those exceptional cases where we do use it.
diff --git a/media/engine/simulcast_encoder_adapter.cc b/media/engine/simulcast_encoder_adapter.cc
index 863ccc7..60baed9 100644
--- a/media/engine/simulcast_encoder_adapter.cc
+++ b/media/engine/simulcast_encoder_adapter.cc
@@ -619,6 +619,10 @@
   // TODO(ronghuawu): what to do with targetBitrate.
 
   stream_codec->startBitrate = start_bitrate_kbps;
+
+  // Legacy screenshare mode is only enabled for the first simulcast layer
+  stream_codec->legacy_conference_mode =
+      inst.legacy_conference_mode && stream_index == 0;
 }
 
 bool SimulcastEncoderAdapter::Initialized() const {
diff --git a/media/engine/webrtc_video_engine.cc b/media/engine/webrtc_video_engine.cc
index 26fa335..a075f7b 100644
--- a/media/engine/webrtc_video_engine.cc
+++ b/media/engine/webrtc_video_engine.cc
@@ -2399,6 +2399,8 @@
     }
   }
 
+  encoder_config.legacy_conference_mode = parameters_.conference_mode;
+
   int max_qp = kDefaultQpMax;
   codec.GetParam(kCodecParamMaxQuantization, &max_qp);
   encoder_config.video_stream_factory =
@@ -3394,7 +3396,7 @@
       ((absl::EqualsIgnoreCase(codec_name_, kVp8CodecName) ||
         absl::EqualsIgnoreCase(codec_name_, kH264CodecName)) &&
        is_screenshare_ && conference_mode_)) {
-    return CreateSimulcastOrConfereceModeScreenshareStreams(
+    return CreateSimulcastOrConferenceModeScreenshareStreams(
         width, height, encoder_config, experimental_min_bitrate);
   }
 
@@ -3483,7 +3485,7 @@
 }
 
 std::vector<webrtc::VideoStream>
-EncoderStreamFactory::CreateSimulcastOrConfereceModeScreenshareStreams(
+EncoderStreamFactory::CreateSimulcastOrConferenceModeScreenshareStreams(
     int width,
     int height,
     const webrtc::VideoEncoderConfig& encoder_config,
diff --git a/media/engine/webrtc_video_engine.h b/media/engine/webrtc_video_engine.h
index 21033ff..9737dd8 100644
--- a/media/engine/webrtc_video_engine.h
+++ b/media/engine/webrtc_video_engine.h
@@ -661,7 +661,7 @@
       const absl::optional<webrtc::DataRate>& experimental_min_bitrate) const;
 
   std::vector<webrtc::VideoStream>
-  CreateSimulcastOrConfereceModeScreenshareStreams(
+  CreateSimulcastOrConferenceModeScreenshareStreams(
       int width,
       int height,
       const webrtc::VideoEncoderConfig& encoder_config,
diff --git a/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc b/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
index ac04bc3..9b64d16 100644
--- a/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
+++ b/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
@@ -879,7 +879,7 @@
   const int encoder_id = encoders_.size() - 1 - sid;
   size_t bitrate_bps;
   float fps;
-  if (SimulcastUtility::IsConferenceModeScreenshare(codec_) ||
+  if ((SimulcastUtility::IsConferenceModeScreenshare(codec_) && sid == 0) ||
       vpx_configs_[encoder_id].ts_number_layers <= 1) {
     // In conference screenshare there's no defined per temporal layer bitrate
     // and framerate.
diff --git a/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc b/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc
index 5159526..d3e4a17 100644
--- a/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc
+++ b/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc
@@ -523,6 +523,7 @@
   codec_settings_.maxBitrate = 1000;
   codec_settings_.mode = VideoCodecMode::kScreensharing;
   codec_settings_.VP8()->numberOfTemporalLayers = 2;
+  codec_settings_.legacy_conference_mode = true;
 
   EXPECT_CALL(*vpx, img_wrap(_, _, _, _, _, _))
       .WillOnce(Invoke([](vpx_image_t* img, vpx_img_fmt_t fmt, unsigned int d_w,
@@ -653,6 +654,7 @@
   codec_settings_.simulcastStream[0].maxBitrate =
       kLegacyScreenshareTl1BitrateKbps;
   codec_settings_.simulcastStream[0].numberOfTemporalLayers = 2;
+  codec_settings_.legacy_conference_mode = true;
   EXPECT_EQ(WEBRTC_VIDEO_CODEC_OK,
             encoder_->InitEncode(&codec_settings_, kSettings));
 
diff --git a/modules/video_coding/utility/simulcast_rate_allocator.cc b/modules/video_coding/utility/simulcast_rate_allocator.cc
index fef74cd..13de875 100644
--- a/modules/video_coding/utility/simulcast_rate_allocator.cc
+++ b/modules/video_coding/utility/simulcast_rate_allocator.cc
@@ -61,7 +61,8 @@
 SimulcastRateAllocator::SimulcastRateAllocator(const VideoCodec& codec)
     : codec_(codec),
       stable_rate_settings_(StableTargetRateExperiment::ParseFromFieldTrials()),
-      rate_control_settings_(RateControlSettings::ParseFromFieldTrials()) {}
+      rate_control_settings_(RateControlSettings::ParseFromFieldTrials()),
+      legacy_conference_mode_(false) {}
 
 SimulcastRateAllocator::~SimulcastRateAllocator() = default;
 
@@ -228,12 +229,7 @@
     uint32_t max_bitrate_kbps;
     // Legacy temporal-layered only screenshare, or simulcast screenshare
     // with legacy mode for simulcast stream 0.
-    const bool conference_screenshare_mode =
-        codec_.mode == VideoCodecMode::kScreensharing &&
-        ((num_spatial_streams == 1 && num_temporal_streams == 2) ||  // Legacy.
-         (num_spatial_streams > 1 && simulcast_id == 0 &&
-          num_temporal_streams == 2));  // Simulcast.
-    if (conference_screenshare_mode) {
+    if (legacy_conference_mode_ && simulcast_id == 0) {
       // TODO(holmer): This is a "temporary" hack for screensharing, where we
       // interpret the startBitrate as the encoder target bitrate. This is
       // to allow for a different max bitrate, so if the codec can't meet
@@ -253,7 +249,7 @@
     if (num_temporal_streams == 1) {
       tl_allocation.push_back(target_bitrate_kbps);
     } else {
-      if (conference_screenshare_mode) {
+      if (legacy_conference_mode_ && simulcast_id == 0) {
         tl_allocation = ScreenshareTemporalLayerAllocation(
             target_bitrate_kbps, max_bitrate_kbps, simulcast_id);
       } else {
@@ -338,4 +334,8 @@
           : codec_.simulcastStream[simulcast_id].numberOfTemporalLayers);
 }
 
+void SimulcastRateAllocator::SetLegacyConferenceMode(bool enabled) {
+  legacy_conference_mode_ = enabled;
+}
+
 }  // namespace webrtc
diff --git a/modules/video_coding/utility/simulcast_rate_allocator.h b/modules/video_coding/utility/simulcast_rate_allocator.h
index d9d9627..9b2f969 100644
--- a/modules/video_coding/utility/simulcast_rate_allocator.h
+++ b/modules/video_coding/utility/simulcast_rate_allocator.h
@@ -38,6 +38,8 @@
                                          int temporal_id,
                                          bool base_heavy_tl3_alloc);
 
+  void SetLegacyConferenceMode(bool mode) override;
+
  private:
   void DistributeAllocationToSimulcastLayers(
       DataRate total_bitrate,
@@ -58,6 +60,7 @@
   const StableTargetRateExperiment stable_rate_settings_;
   const RateControlSettings rate_control_settings_;
   std::vector<bool> stream_enabled_;
+  bool legacy_conference_mode_;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(SimulcastRateAllocator);
 };
diff --git a/modules/video_coding/utility/simulcast_rate_allocator_unittest.cc b/modules/video_coding/utility/simulcast_rate_allocator_unittest.cc
index 871e5a1..69c14ff 100644
--- a/modules/video_coding/utility/simulcast_rate_allocator_unittest.cc
+++ b/modules/video_coding/utility/simulcast_rate_allocator_unittest.cc
@@ -88,8 +88,9 @@
     EXPECT_EQ(sum, actual.get_sum_bps());
   }
 
-  void CreateAllocator() {
+  void CreateAllocator(bool legacy_conference_mode = false) {
     allocator_.reset(new SimulcastRateAllocator(codec_));
+    allocator_->SetLegacyConferenceMode(legacy_conference_mode);
   }
 
   void SetupCodec3SL3TL(const std::vector<bool>& active_streams) {
@@ -669,9 +670,9 @@
                          ScreenshareRateAllocationTest,
                          ::testing::Bool());
 
-TEST_P(ScreenshareRateAllocationTest, BitrateBelowTl0) {
+TEST_P(ScreenshareRateAllocationTest, ConferenceBitrateBelowTl0) {
   SetupConferenceScreenshare(GetParam());
-  CreateAllocator();
+  CreateAllocator(true);
 
   VideoBitrateAllocation allocation =
       allocator_->Allocate(VideoBitrateAllocationParameters(
@@ -684,9 +685,9 @@
   EXPECT_EQ(allocation.is_bw_limited(), GetParam());
 }
 
-TEST_P(ScreenshareRateAllocationTest, BitrateAboveTl0) {
+TEST_P(ScreenshareRateAllocationTest, ConferenceBitrateAboveTl0) {
   SetupConferenceScreenshare(GetParam());
-  CreateAllocator();
+  CreateAllocator(true);
 
   uint32_t target_bitrate_kbps =
       (kLegacyScreenshareTargetBitrateKbps + kLegacyScreenshareMaxBitrateKbps) /
@@ -704,10 +705,10 @@
   EXPECT_EQ(allocation.is_bw_limited(), GetParam());
 }
 
-TEST_F(ScreenshareRateAllocationTest, BitrateAboveTl1) {
+TEST_F(ScreenshareRateAllocationTest, ConferenceBitrateAboveTl1) {
   // This test is only for the non-simulcast case.
   SetupConferenceScreenshare(false);
-  CreateAllocator();
+  CreateAllocator(true);
 
   VideoBitrateAllocation allocation =
       allocator_->Allocate(VideoBitrateAllocationParameters(
diff --git a/modules/video_coding/utility/simulcast_utility.cc b/modules/video_coding/utility/simulcast_utility.cc
index 58cb991..a407483 100644
--- a/modules/video_coding/utility/simulcast_utility.cc
+++ b/modules/video_coding/utility/simulcast_utility.cc
@@ -84,16 +84,8 @@
 }
 
 bool SimulcastUtility::IsConferenceModeScreenshare(const VideoCodec& codec) {
-  if (codec.mode != VideoCodecMode::kScreensharing ||
-      NumberOfTemporalLayers(codec, 0) != 2) {
-    return false;
-  }
-
-  // Fixed default bitrates for legacy screenshare layers mode.
-  return (codec.numberOfSimulcastStreams == 0 && codec.maxBitrate == 1000) ||
-         (codec.numberOfSimulcastStreams >= 1 &&
-          codec.simulcastStream[0].maxBitrate == 1000 &&
-          codec.simulcastStream[0].targetBitrate == 200);
+  return codec.mode == VideoCodecMode::kScreensharing &&
+         codec.legacy_conference_mode;
 }
 
 int SimulcastUtility::NumberOfTemporalLayers(const VideoCodec& codec,
diff --git a/modules/video_coding/video_codec_initializer.cc b/modules/video_coding/video_codec_initializer.cc
index 7f36f99..4023f6b 100644
--- a/modules/video_coding/video_codec_initializer.cc
+++ b/modules/video_coding/video_codec_initializer.cc
@@ -68,6 +68,10 @@
       break;
   }
 
+  video_codec.legacy_conference_mode =
+      config.content_type == VideoEncoderConfig::ContentType::kScreen &&
+      config.legacy_conference_mode;
+
   // TODO(nisse): The plType field should be deleted. Luckily, our
   // callers don't need it.
   video_codec.plType = 0;
diff --git a/modules/video_coding/video_codec_initializer_unittest.cc b/modules/video_coding/video_codec_initializer_unittest.cc
index d5a18f0..686396c 100644
--- a/modules/video_coding/video_codec_initializer_unittest.cc
+++ b/modules/video_coding/video_codec_initializer_unittest.cc
@@ -42,7 +42,8 @@
 static const uint32_t kDefaultMaxBitrateBps = 2000000;
 static const uint32_t kDefaultMinTransmitBitrateBps = 400000;
 static const int kDefaultMaxQp = 48;
-static const uint32_t kScreenshareTl0BitrateBps = 200000;
+static const uint32_t kScreenshareTl0BitrateBps = 120000;
+static const uint32_t kScreenshareConferenceTl0BitrateBps = 200000;
 static const uint32_t kScreenshareCodecTargetBitrateBps = 200000;
 static const uint32_t kScreenshareDefaultFramerate = 5;
 // Bitrates for the temporal layers of the higher screenshare simulcast stream.
@@ -126,7 +127,7 @@
   VideoStream DefaultScreenshareStream() {
     VideoStream stream = DefaultStream();
     stream.min_bitrate_bps = 30000;
-    stream.target_bitrate_bps = kScreenshareTl0BitrateBps;
+    stream.target_bitrate_bps = kScreenshareCodecTargetBitrateBps;
     stream.max_bitrate_bps = 1000000;
     stream.max_framerate = kScreenshareDefaultFramerate;
     stream.num_temporal_layers = 2;
@@ -174,6 +175,23 @@
   EXPECT_EQ(0U, bitrate_allocation.get_sum_bps());
 }
 
+TEST_F(VideoCodecInitializerTest, TemporalLayeredVp8ScreenshareConference) {
+  SetUpFor(VideoCodecType::kVideoCodecVP8, 1, 2, true);
+  streams_.push_back(DefaultScreenshareStream());
+  EXPECT_TRUE(InitializeCodec());
+  bitrate_allocator_->SetLegacyConferenceMode(true);
+
+  EXPECT_EQ(1u, codec_out_.numberOfSimulcastStreams);
+  EXPECT_EQ(2u, codec_out_.VP8()->numberOfTemporalLayers);
+  VideoBitrateAllocation bitrate_allocation =
+      bitrate_allocator_->Allocate(VideoBitrateAllocationParameters(
+          kScreenshareCodecTargetBitrateBps, kScreenshareDefaultFramerate));
+  EXPECT_EQ(kScreenshareCodecTargetBitrateBps,
+            bitrate_allocation.get_sum_bps());
+  EXPECT_EQ(kScreenshareConferenceTl0BitrateBps,
+            bitrate_allocation.GetBitrate(0, 0));
+}
+
 TEST_F(VideoCodecInitializerTest, TemporalLayeredVp8Screenshare) {
   SetUpFor(VideoCodecType::kVideoCodecVP8, 1, 2, true);
   streams_.push_back(DefaultScreenshareStream());
diff --git a/video/video_stream_encoder.cc b/video/video_stream_encoder.cc
index 80b7963..f38d2a2 100644
--- a/video/video_stream_encoder.cc
+++ b/video/video_stream_encoder.cc
@@ -780,6 +780,8 @@
 
   rate_allocator_ =
       settings_.bitrate_allocator_factory->CreateVideoBitrateAllocator(codec);
+  rate_allocator_->SetLegacyConferenceMode(
+      encoder_config_.legacy_conference_mode);
 
   // Reset (release existing encoder) if one exists and anything except
   // start bitrate or max framerate has changed.