diff --git a/dom/chrome-webidl/MediaController.webidl b/dom/chrome-webidl/MediaController.webidl
index b16282877ae8..66467ec19954 100644
--- a/dom/chrome-webidl/MediaController.webidl
+++ b/dom/chrome-webidl/MediaController.webidl
@@ -54,8 +54,8 @@ interface MediaController : EventTarget {
   undefined stop();
   undefined prevTrack();
   undefined nextTrack();
-  undefined seekBackward();
-  undefined seekForward();
+  undefined seekBackward(double seekOffset);
+  undefined seekForward(double seekOffset);
   undefined skipAd();
   undefined seekTo(double seekTime, optional boolean fastSeek = false);
 };
diff --git a/dom/media/mediacontrol/ContentPlaybackController.cpp b/dom/media/mediacontrol/ContentPlaybackController.cpp
index ba06ea1cdbec..a48d5eaedc27 100644
--- a/dom/media/mediacontrol/ContentPlaybackController.cpp
+++ b/dom/media/mediacontrol/ContentPlaybackController.cpp
@@ -120,12 +120,22 @@ void ContentPlaybackController::Pause() {
   }
 }
 
-void ContentPlaybackController::SeekBackward() {
-  NotifyMediaSessionWhenActionIsSupported(MediaSessionAction::Seekbackward);
+void ContentPlaybackController::SeekBackward(double aSeekOffset) {
+  MediaSessionActionDetails details;
+  details.mAction = MediaSessionAction::Seekbackward;
+  details.mSeekOffset.Construct(aSeekOffset);
+  if (IsMediaSessionActionSupported(details.mAction)) {
+    NotifyMediaSession(details);
+  }
 }
 
-void ContentPlaybackController::SeekForward() {
-  NotifyMediaSessionWhenActionIsSupported(MediaSessionAction::Seekforward);
+void ContentPlaybackController::SeekForward(double aSeekOffset) {
+  MediaSessionActionDetails details;
+  details.mAction = MediaSessionAction::Seekforward;
+  details.mSeekOffset.Construct(aSeekOffset);
+  if (IsMediaSessionActionSupported(details.mAction)) {
+    NotifyMediaSession(details);
+  }
 }
 
 void ContentPlaybackController::PreviousTrack() {
@@ -195,18 +205,26 @@ void ContentMediaControlKeyHandler::HandleMediaControlAction(
     case MediaControlKey::Nexttrack:
       controller.NextTrack();
       return;
-    case MediaControlKey::Seekbackward:
-      controller.SeekBackward();
+    case MediaControlKey::Seekbackward: {
+      const SeekDetails& details = *aAction.mDetails;
+      MOZ_ASSERT(details.mRelativeSeekOffset);
+      controller.SeekBackward(details.mRelativeSeekOffset.value());
       return;
-    case MediaControlKey::Seekforward:
-      controller.SeekForward();
+    }
+    case MediaControlKey::Seekforward: {
+      const SeekDetails& details = *aAction.mDetails;
+      MOZ_ASSERT(details.mRelativeSeekOffset);
+      controller.SeekForward(details.mRelativeSeekOffset.value());
       return;
+    }
     case MediaControlKey::Skipad:
       controller.SkipAd();
       return;
     case MediaControlKey::Seekto: {
       const SeekDetails& details = *aAction.mDetails;
-      controller.SeekTo(details.mSeekTime, details.mFastSeek);
+      MOZ_ASSERT(details.mAbsolute);
+      controller.SeekTo(details.mAbsolute->mSeekTime,
+                        details.mAbsolute->mFastSeek);
       return;
     }
     default:
diff --git a/dom/media/mediacontrol/ContentPlaybackController.h b/dom/media/mediacontrol/ContentPlaybackController.h
index a692dedde049..8b8e66e234f9 100644
--- a/dom/media/mediacontrol/ContentPlaybackController.h
+++ b/dom/media/mediacontrol/ContentPlaybackController.h
@@ -42,8 +42,8 @@ class MOZ_STACK_CLASS ContentPlaybackController {
   MOZ_CAN_RUN_SCRIPT_BOUNDARY void Focus();
   void Play();
   void Pause();
-  void SeekBackward();
-  void SeekForward();
+  void SeekBackward(double aSeekOffset);
+  void SeekForward(double aSeekOffset);
   void PreviousTrack();
   void NextTrack();
   void SkipAd();
diff --git a/dom/media/mediacontrol/MediaControlIPC.h b/dom/media/mediacontrol/MediaControlIPC.h
index 100e5832c222..71082dc1385e 100644
--- a/dom/media/mediacontrol/MediaControlIPC.h
+++ b/dom/media/mediacontrol/MediaControlIPC.h
@@ -35,8 +35,8 @@ struct ParamTraits<mozilla::dom::MediaAudibleState>
           mozilla::dom::MediaAudibleState::eAudible> {};
 
 template <>
-struct ParamTraits<mozilla::dom::SeekDetails> {
-  typedef mozilla::dom::SeekDetails paramType;
+struct ParamTraits<mozilla::dom::AbsoluteSeek> {
+  typedef mozilla::dom::AbsoluteSeek paramType;
 
   static void Write(MessageWriter* aWriter, const paramType& aParam) {
     WriteParam(aWriter, aParam.mSeekTime);
@@ -52,6 +52,24 @@ struct ParamTraits<mozilla::dom::SeekDetails> {
   }
 };
 
+template <>
+struct ParamTraits<mozilla::dom::SeekDetails> {
+  typedef mozilla::dom::SeekDetails paramType;
+
+  static void Write(MessageWriter* aWriter, const paramType& aParam) {
+    WriteParam(aWriter, aParam.mAbsolute);
+    WriteParam(aWriter, aParam.mRelativeSeekOffset);
+  }
+
+  static bool Read(MessageReader* aReader, paramType* aResult) {
+    if (!ReadParam(aReader, &aResult->mAbsolute) ||
+        !ReadParam(aReader, &aResult->mRelativeSeekOffset)) {
+      return false;
+    }
+    return true;
+  }
+};
+
 template <>
 struct ParamTraits<mozilla::dom::MediaControlAction> {
   typedef mozilla::dom::MediaControlAction paramType;
diff --git a/dom/media/mediacontrol/MediaControlKeySource.cpp b/dom/media/mediacontrol/MediaControlKeySource.cpp
index db372fc57b56..d57d6853ba96 100644
--- a/dom/media/mediacontrol/MediaControlKeySource.cpp
+++ b/dom/media/mediacontrol/MediaControlKeySource.cpp
@@ -64,18 +64,26 @@ void MediaControlKeyHandler::OnActionPerformed(
     case MediaControlKey::Nexttrack:
       controller->NextTrack();
       return;
-    case MediaControlKey::Seekbackward:
-      controller->SeekBackward();
+    case MediaControlKey::Seekbackward: {
+      const SeekDetails& details = *aAction.mDetails;
+      MOZ_ASSERT(details.mRelativeSeekOffset);
+      controller->SeekBackward(fmin(details.mRelativeSeekOffset.value(), 10.0));
       return;
-    case MediaControlKey::Seekforward:
-      controller->SeekForward();
+    }
+    case MediaControlKey::Seekforward: {
+      const SeekDetails& details = *aAction.mDetails;
+      MOZ_ASSERT(details.mRelativeSeekOffset);
+      controller->SeekForward(fmin(details.mRelativeSeekOffset.value(), 10.0));
       return;
+    }
     case MediaControlKey::Skipad:
       controller->SkipAd();
       return;
     case MediaControlKey::Seekto: {
       const SeekDetails& details = *aAction.mDetails;
-      controller->SeekTo(details.mSeekTime, details.mFastSeek);
+      MOZ_ASSERT(details.mAbsolute);
+      controller->SeekTo(details.mAbsolute->mSeekTime,
+                         details.mAbsolute->mFastSeek);
       return;
     }
     case MediaControlKey::Stop:
diff --git a/dom/media/mediacontrol/MediaControlKeySource.h b/dom/media/mediacontrol/MediaControlKeySource.h
index a3261b31f9fe..f05448ca898b 100644
--- a/dom/media/mediacontrol/MediaControlKeySource.h
+++ b/dom/media/mediacontrol/MediaControlKeySource.h
@@ -5,6 +5,7 @@
 #ifndef DOM_MEDIA_MEDIACONTROL_MEDIACONTROLKEYSOURCE_H_
 #define DOM_MEDIA_MEDIACONTROL_MEDIACONTROLKEYSOURCE_H_
 
+#include "mozilla/Maybe.h"
 #include "mozilla/dom/MediaControllerBinding.h"
 #include "mozilla/dom/MediaMetadata.h"
 #include "mozilla/dom/MediaSession.h"
@@ -15,15 +16,20 @@
 namespace mozilla::dom {
 
 // This is used to store seek related properties from MediaSessionActionDetails.
-// However, currently we have no plan to support `seekOffset`.
 // https://w3c.github.io/mediasession/#the-mediasessionactiondetails-dictionary
+struct AbsoluteSeek {
+  double mSeekTime;
+  bool mFastSeek;
+};
 struct SeekDetails {
+  Maybe<AbsoluteSeek> mAbsolute;
+  Maybe<double> mRelativeSeekOffset;
+
   SeekDetails() = default;
-  explicit SeekDetails(double aSeekTime) : mSeekTime(aSeekTime) {}
   SeekDetails(double aSeekTime, bool aFastSeek)
-      : mSeekTime(aSeekTime), mFastSeek(aFastSeek) {}
-  double mSeekTime = 0.0;
-  bool mFastSeek = false;
+      : mAbsolute(Some(AbsoluteSeek{aSeekTime, aFastSeek})) {}
+  explicit SeekDetails(double aRelativeSeekOffset)
+      : mRelativeSeekOffset(Some(aRelativeSeekOffset)) {}
 };
 
 struct MediaControlAction {
diff --git a/dom/media/mediacontrol/MediaControlService.cpp b/dom/media/mediacontrol/MediaControlService.cpp
index c64749f55640..3fca926175af 100644
--- a/dom/media/mediacontrol/MediaControlService.cpp
+++ b/dom/media/mediacontrol/MediaControlService.cpp
@@ -307,12 +307,19 @@ void MediaControlService::GenerateTestMediaControlKey(MediaControlKey aKey) {
   if (!StaticPrefs::media_mediacontrol_testingevents_enabled()) {
     return;
   }
-  // Generate a seek details for `seekto`
-  if (aKey == MediaControlKey::Seekto) {
-    mMediaKeysHandler->OnActionPerformed(
-        MediaControlAction(aKey, SeekDetails()));
-  } else {
-    mMediaKeysHandler->OnActionPerformed(MediaControlAction(aKey));
+  // Generate seek details when necessary
+  switch (aKey) {
+    case MediaControlKey::Seekto:
+      mMediaKeysHandler->OnActionPerformed(
+          MediaControlAction(aKey, SeekDetails(0.0, false /* fast seek */)));
+      break;
+    case MediaControlKey::Seekbackward:
+    case MediaControlKey::Seekforward:
+      mMediaKeysHandler->OnActionPerformed(
+          MediaControlAction(aKey, SeekDetails(0.0)));
+      break;
+    default:
+      mMediaKeysHandler->OnActionPerformed(MediaControlAction(aKey));
   }
 }
 
diff --git a/dom/media/mediacontrol/MediaController.cpp b/dom/media/mediacontrol/MediaController.cpp
index 4290e952b01c..a0443423807f 100644
--- a/dom/media/mediacontrol/MediaController.cpp
+++ b/dom/media/mediacontrol/MediaController.cpp
@@ -142,16 +142,16 @@ void MediaController::NextTrack() {
       MediaControlAction(MediaControlKey::Nexttrack));
 }
 
-void MediaController::SeekBackward() {
+void MediaController::SeekBackward(double aSeekOffset) {
   LOG("Seek Backward");
-  UpdateMediaControlActionToContentMediaIfNeeded(
-      MediaControlAction(MediaControlKey::Seekbackward));
+  UpdateMediaControlActionToContentMediaIfNeeded(MediaControlAction(
+      MediaControlKey::Seekbackward, SeekDetails(aSeekOffset)));
 }
 
-void MediaController::SeekForward() {
+void MediaController::SeekForward(double aSeekOffset) {
   LOG("Seek Forward");
-  UpdateMediaControlActionToContentMediaIfNeeded(
-      MediaControlAction(MediaControlKey::Seekforward));
+  UpdateMediaControlActionToContentMediaIfNeeded(MediaControlAction(
+      MediaControlKey::Seekforward, SeekDetails(aSeekOffset)));
 }
 
 void MediaController::SkipAd() {
diff --git a/dom/media/mediacontrol/MediaController.h b/dom/media/mediacontrol/MediaController.h
index f95ff6368e23..8fec9c59e38b 100644
--- a/dom/media/mediacontrol/MediaController.h
+++ b/dom/media/mediacontrol/MediaController.h
@@ -36,8 +36,8 @@ class IMediaController {
   virtual void Stop() = 0;
   virtual void PrevTrack() = 0;
   virtual void NextTrack() = 0;
-  virtual void SeekBackward() = 0;
-  virtual void SeekForward() = 0;
+  virtual void SeekBackward(double aSeekOffset) = 0;
+  virtual void SeekForward(double aSeekOffset) = 0;
   virtual void SkipAd() = 0;
   virtual void SeekTo(double aSeekTime, bool aFastSeek) = 0;
 
@@ -104,8 +104,8 @@ class MediaController final : public DOMEventTargetHelper,
   void Stop() override;
   void PrevTrack() override;
   void NextTrack() override;
-  void SeekBackward() override;
-  void SeekForward() override;
+  void SeekBackward(double aSeekOffset) override;
+  void SeekForward(double aSeekOffset) override;
   void SkipAd() override;
   void SeekTo(double aSeekTime, bool aFastSeek) override;
 
diff --git a/dom/media/mediacontrol/tests/browser/browser.toml b/dom/media/mediacontrol/tests/browser/browser.toml
index 2e7b642737b6..7fc5e6ebad3b 100644
--- a/dom/media/mediacontrol/tests/browser/browser.toml
+++ b/dom/media/mediacontrol/tests/browser/browser.toml
@@ -50,7 +50,7 @@ skip-if = ["verify && os == 'mac'"] # bug 1673509
 ["browser_media_control_position_state.js"]
 skip-if = ["apple_catalina && !debug"] # Bug 1775892
 
-["browser_media_control_seekto.js"]
+["browser_media_control_seek.js"]
 
 ["browser_media_control_stop_timer.js"]
 
diff --git a/dom/media/mediacontrol/tests/browser/browser_media_control_seekto.js b/dom/media/mediacontrol/tests/browser/browser_media_control_seek.js
similarity index 59%
rename from dom/media/mediacontrol/tests/browser/browser_media_control_seekto.js
rename to dom/media/mediacontrol/tests/browser/browser_media_control_seek.js
index 7502c6d1b1db..aa2fe1eba936 100644
--- a/dom/media/mediacontrol/tests/browser/browser_media_control_seekto.js
+++ b/dom/media/mediacontrol/tests/browser/browser_media_control_seek.js
@@ -28,7 +28,7 @@ add_task(async function testSetPositionState() {
     seekTime: seektime,
   });
 
-  info(`seek to ${seektime} seconds and set fastseek to boolean`);
+  info(`seek to ${seektime} seconds and set fastseek to true`);
   await PerformSeekTo(tab, {
     seekTime: seektime,
     fastSeek: true,
@@ -44,6 +44,28 @@ add_task(async function testSetPositionState() {
   await tab.close();
 });
 
+add_task(async function testSeekRelative() {
+  info(`open media page`);
+  const tab = await createLoadedTabWrapper(PAGE_URL);
+
+  info(`start media`);
+  await playMedia(tab, testVideoId);
+
+  const seekoffset = 5;
+  info(`seek forward ${seekoffset} seconds`);
+  await PerformSeekRelative(tab, "seekforward", {
+    seekOffset: seekoffset,
+  });
+
+  info(`seek backward ${seekoffset} seconds`);
+  await PerformSeekRelative(tab, "seekbackward", {
+    seekOffset: seekoffset,
+  });
+
+  info(`remove tab`);
+  await tab.close();
+});
+
 /**
  * The following is helper function.
  */
@@ -82,10 +104,46 @@ async function PerformSeekTo(tab, seekDetails) {
     [testVideoId],
     Id => {
       const video = content.document.getElementById(Id);
-      return new Promise(r => (video.onseeking = r()));
+      return new Promise(r => (video.onseeked = r()));
     }
   );
   const { seekTime, fastSeek } = seekDetails;
   tab.linkedBrowser.browsingContext.mediaController.seekTo(seekTime, fastSeek);
   await seekPromise;
 }
+
+async function PerformSeekRelative(tab, mode, seekDetails) {
+  await SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [seekDetails, mode, testVideoId],
+    (seekDetails, mode, Id) => {
+      const { seekOffset } = seekDetails;
+      content.navigator.mediaSession.setActionHandler(mode, details => {
+        Assert.notEqual(
+          details.seekOffset,
+          undefined,
+          "Seekoffset must be presented"
+        );
+        is(seekOffset, details.seekOffset, "Get correct seekoffset");
+
+        content.document.getElementById(Id).currentTime +=
+          mode == "seekForward" ? seekOffset : -seekOffset;
+      });
+    }
+  );
+  const seekPromise = SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [testVideoId],
+    Id => {
+      const video = content.document.getElementById(Id);
+      return new Promise(r => (video.onseeked = r()));
+    }
+  );
+  const { seekOffset } = seekDetails;
+  if (mode === "seekforward") {
+    tab.linkedBrowser.browsingContext.mediaController.seekForward(seekOffset);
+  } else {
+    tab.linkedBrowser.browsingContext.mediaController.seekBackward(seekOffset);
+  }
+  await seekPromise;
+}
diff --git a/widget/gtk/MPRISServiceHandler.cpp b/widget/gtk/MPRISServiceHandler.cpp
index f8265be79135..a100b747f2fd 100644
--- a/widget/gtk/MPRISServiceHandler.cpp
+++ b/widget/gtk/MPRISServiceHandler.cpp
@@ -49,7 +49,9 @@ static inline Maybe<dom::MediaControlKey> GetMediaControlKey(
       {"Pause", dom::MediaControlKey::Pause},
       {"PlayPause", dom::MediaControlKey::Playpause},
       {"Stop", dom::MediaControlKey::Stop},
-      {"Play", dom::MediaControlKey::Play}};
+      {"Play", dom::MediaControlKey::Play},
+      {"SetPosition", dom::MediaControlKey::Seekto},
+      {"Seek", dom::MediaControlKey::Seekforward}};
 
   auto it = map.find(aMethodName);
   return it == map.end() ? Nothing() : Some(it->second);
@@ -73,8 +75,33 @@ static void HandleMethodCall(GDBusConnection* aConnection, const gchar* aSender,
     return;
   }
 
+  dom::SeekDetails seekDetails{};
+  if (key.value() == dom::MediaControlKey::Seekto ||
+      key.value() == dom::MediaControlKey::Seekforward) {
+    RefPtr<GVariant> child = dont_AddRef(g_variant_get_child_value(
+        aParameters, key.value() == dom::MediaControlKey::Seekto));
+    double seekValue;
+    if (g_variant_is_of_type(child, G_VARIANT_TYPE_INT64)) {
+      seekValue = (double)g_variant_get_int64(child) / 1000000.0;
+    } else {
+      g_dbus_method_invocation_return_error(
+          aInvocation, G_DBUS_ERROR, G_DBUS_ERROR_INVALID_ARGS,
+          "Invalid arguments for %s.%s.%s", aObjectPath, aInterfaceName,
+          aMethodName);
+      return;
+    }
+    if (key.value() == dom::MediaControlKey::Seekto) {
+      seekDetails = dom::SeekDetails(seekValue, false /* fast seek */);
+    } else if (seekValue > 0.0) {
+      seekDetails = dom::SeekDetails(seekValue);
+    } else {
+      key = Some(dom::MediaControlKey::Seekbackward);
+      seekDetails = dom::SeekDetails(-1 * seekValue);
+    }
+  }
+
   MPRISServiceHandler* handler = static_cast<MPRISServiceHandler*>(aUserData);
-  if (handler->PressKey(key.value())) {
+  if (handler->PressKey(dom::MediaControlAction(key.value(), seekDetails))) {
     g_dbus_method_invocation_return_value(aInvocation, nullptr);
   } else {
     g_dbus_method_invocation_return_error(
@@ -100,6 +127,7 @@ enum class Property : uint8_t {
   eCanControl,
   eGetPlaybackStatus,
   eGetMetadata,
+  eGetPosition,
 };
 
 static inline Maybe<dom::MediaControlKey> GetPairedKey(Property aProperty) {
@@ -137,7 +165,8 @@ static inline Maybe<Property> GetProperty(const gchar* aPropertyName) {
       {"CanSeek", Property::eCanSeek},
       {"CanControl", Property::eCanControl},
       {"PlaybackStatus", Property::eGetPlaybackStatus},
-      {"Metadata", Property::eGetMetadata}};
+      {"Metadata", Property::eGetMetadata},
+      {"Position", Property::eGetPosition}};
 
   auto it = map.find(aPropertyName);
   return (it == map.end() ? Nothing() : Some(it->second));
@@ -170,16 +199,21 @@ static GVariant* HandleGetProperty(GDBusConnection* aConnection,
       return handler->GetPlaybackStatus();
     case Property::eGetMetadata:
       return handler->GetMetadataAsGVariant();
+    case Property::eGetPosition: {
+      CheckedInt64 position =
+          CheckedInt64((int64_t)handler->GetPositionSeconds()) * 1000000;
+      return g_variant_new_int64(position.isValid() ? position.value() : 0);
+    }
     case Property::eIdentity:
       return g_variant_new_string(handler->Identity());
     case Property::eDesktopEntry:
       return g_variant_new_string(handler->DesktopEntry());
     case Property::eHasTrackList:
     case Property::eCanQuit:
-    case Property::eCanSeek:
       return g_variant_new_boolean(false);
     // Play/Pause would be blocked if CanControl is false
     case Property::eCanControl:
+    case Property::eCanSeek:
       return g_variant_new_boolean(true);
     case Property::eCanRaise:
     case Property::eCanGoNext:
@@ -443,14 +477,16 @@ const char* MPRISServiceHandler::DesktopEntry() const {
   return mDesktopEntry.get();
 }
 
-bool MPRISServiceHandler::PressKey(dom::MediaControlKey aKey) const {
+bool MPRISServiceHandler::PressKey(
+    const dom::MediaControlAction& aAction) const {
   MOZ_ASSERT(mInitialized);
-  if (!IsMediaKeySupported(aKey)) {
-    LOGMPRIS("%s is not supported", dom::GetEnumString(aKey).get());
+  if (!IsMediaKeySupported(aAction.mKey.value())) {
+    LOGMPRIS("%s is not supported",
+             dom::GetEnumString(aAction.mKey.value()).get());
     return false;
   }
-  LOGMPRIS("Press %s", dom::GetEnumString(aKey).get());
-  EmitEvent(aKey);
+  LOGMPRIS("Press %s", dom::GetEnumString(aAction.mKey.value()).get());
+  EmitEvent(aAction);
   return true;
 }
 
@@ -812,9 +848,10 @@ GVariant* MPRISServiceHandler::GetMetadataAsGVariant() const {
   return g_variant_builder_end(&builder);
 }
 
-void MPRISServiceHandler::EmitEvent(dom::MediaControlKey aKey) const {
+void MPRISServiceHandler::EmitEvent(
+    const dom::MediaControlAction& aAction) const {
   for (const auto& listener : mListeners) {
-    listener->OnActionPerformed(dom::MediaControlAction(aKey));
+    listener->OnActionPerformed(aAction);
   }
 }
 
@@ -860,6 +897,18 @@ void MPRISServiceHandler::SetSupportedMediaKeys(
   }
 }
 
+void MPRISServiceHandler::SetPositionState(
+    const Maybe<dom::PositionState>& aState) {
+  mPositionState = aState;
+}
+
+double MPRISServiceHandler::GetPositionSeconds() const {
+  if (mPositionState.isSome()) {
+    return mPositionState.value().CurrentPlaybackPosition();
+  }
+  return 0.0;
+}
+
 bool MPRISServiceHandler::IsMediaKeySupported(dom::MediaControlKey aKey) const {
   return mSupportedKeys & GetMediaKeyMask(aKey);
 }
diff --git a/widget/gtk/MPRISServiceHandler.h b/widget/gtk/MPRISServiceHandler.h
index 469090efc028..924693d4cfd5 100644
--- a/widget/gtk/MPRISServiceHandler.h
+++ b/widget/gtk/MPRISServiceHandler.h
@@ -72,13 +72,16 @@ class MPRISServiceHandler final : public dom::MediaControlKeySource {
 
   const char* Identity() const;
   const char* DesktopEntry() const;
-  bool PressKey(dom::MediaControlKey aKey) const;
+  bool PressKey(const dom::MediaControlAction& aAction) const;
 
   void SetMediaMetadata(const dom::MediaMetadataBase& aMetadata) override;
   GVariant* GetMetadataAsGVariant() const;
 
   void SetSupportedMediaKeys(const MediaKeysArray& aSupportedKeys) override;
 
+  void SetPositionState(const Maybe<dom::PositionState>& aState) override;
+  double GetPositionSeconds() const;
+
   bool IsMediaKeySupported(dom::MediaControlKey aKey) const;
 
   void OwnName(GDBusConnection* aConnection);
@@ -110,6 +113,8 @@ class MPRISServiceHandler final : public dom::MediaControlKeySource {
   // A bitmask indicating what keys are enabled
   uint32_t mSupportedKeys = 0;
 
+  Maybe<dom::PositionState> mPositionState;
+
   class MPRISMetadata : public dom::MediaMetadataBase {
    public:
     MPRISMetadata() = default;
@@ -168,7 +173,7 @@ class MPRISServiceHandler final : public dom::MediaControlKeySource {
   static void OnBusAcquiredStatic(GDBusConnection* aConnection,
                                   const gchar* aName, gpointer aUserData);
 
-  void EmitEvent(dom::MediaControlKey aKey) const;
+  void EmitEvent(const dom::MediaControlAction& aAction) const;
 
   bool EmitMetadataChanged() const;
 
diff --git a/widget/windows/WindowsSMTCProvider.cpp b/widget/windows/WindowsSMTCProvider.cpp
index 3ddd26b6ccae..8cce5612def6 100644
--- a/widget/windows/WindowsSMTCProvider.cpp
+++ b/widget/windows/WindowsSMTCProvider.cpp
@@ -426,9 +426,9 @@ void WindowsSMTCProvider::OnPositionChangeRequested(double aPosition) const {
   }
 
   for (const auto& listener : mListeners) {
-    listener->OnActionPerformed(
-        mozilla::dom::MediaControlAction(mozilla::dom::MediaControlKey::Seekto,
-                                         mozilla::dom::SeekDetails(aPosition)));
+    listener->OnActionPerformed(mozilla::dom::MediaControlAction(
+        mozilla::dom::MediaControlKey::Seekto,
+        mozilla::dom::SeekDetails(aPosition, false /* fast seek */)));
   }
 }