diff --git a/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.cpp b/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.cpp
index 42d165ed65e23..d77f947b6b8fb 100644
--- a/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.cpp
+++ b/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.cpp
@@ -275,6 +275,17 @@ void MediaPlayerPrivateGStreamerMSE::load(const String& url, MediaSourcePrivateC
     load(mediasourceUri);
 }
 
+FloatSize MediaPlayerPrivateGStreamerMSE::naturalSize() const
+{
+    if (!hasVideo())
+        return FloatSize();
+
+    if (!m_videoSize.isEmpty())
+        return m_videoSize;
+
+    return MediaPlayerPrivateGStreamerBase::naturalSize();
+}
+
 void MediaPlayerPrivateGStreamerMSE::pause()
 {
     m_paused = true;
diff --git a/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.h b/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.h
index 5287e21fc172d..9b89c58bf2085 100644
--- a/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.h
+++ b/Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamerMSE.h
@@ -51,6 +51,8 @@ class MediaPlayerPrivateGStreamerMSE : public MediaPlayerPrivateGStreamer {
     void load(const String &url) override;
     void load(const String& url, MediaSourcePrivateClient*) override;
 
+    FloatSize naturalSize() const override;
+
     void setDownloadBuffering() override { };
 
     bool isLiveStream() const override { return false; }