diff --git a/Tests/LibVideo/CMakeLists.txt b/Tests/LibVideo/CMakeLists.txt
index 4c14e2d7c9e..bd0ba699460 100644
--- a/Tests/LibVideo/CMakeLists.txt
+++ b/Tests/LibVideo/CMakeLists.txt
@@ -9,3 +9,4 @@ endforeach()
 install(FILES vp9_in_webm.webm DESTINATION usr/Tests/LibVideo)
 install(FILES vp9_4k.webm DESTINATION usr/Tests/LibVideo)
 install(FILES vp9_clamp_reference_mvs.webm DESTINATION usr/Tests/LibVideo)
+install(FILES vp9_oob_blocks.webm DESTINATION usr/Tests/LibVideo)
diff --git a/Tests/LibVideo/TestVP9Decode.cpp b/Tests/LibVideo/TestVP9Decode.cpp
index e173f115df5..ac24e8b24eb 100644
--- a/Tests/LibVideo/TestVP9Decode.cpp
+++ b/Tests/LibVideo/TestVP9Decode.cpp
@@ -54,6 +54,11 @@ TEST_CASE(webm_in_vp9)
     decode_video("./vp9_in_webm.webm"sv, 25);
 }
 
+TEST_CASE(vp9_oob_blocks)
+{
+    decode_video("./vp9_oob_blocks.webm"sv, 240);
+}
+
 BENCHMARK_CASE(vp9_4k)
 {
     decode_video("./vp9_4k.webm"sv, 2);
diff --git a/Tests/LibVideo/vp9_oob_blocks.webm b/Tests/LibVideo/vp9_oob_blocks.webm
new file mode 100644
index 00000000000..1c11ae17905
Binary files /dev/null and b/Tests/LibVideo/vp9_oob_blocks.webm differ
diff --git a/Userland/Libraries/LibVideo/VP9/Context.h b/Userland/Libraries/LibVideo/VP9/Context.h
index c543fb3d4f2..9c6b7e7b29b 100644
--- a/Userland/Libraries/LibVideo/VP9/Context.h
+++ b/Userland/Libraries/LibVideo/VP9/Context.h
@@ -105,16 +105,16 @@ public:
     // Calculates the output size for each plane in the frame.
     Gfx::Size<u32> decoded_size(bool uv) const
     {
-        // NOTE: According to the spec, this would be `y_size_to_uv_size(subsampling, blocks_to_pixels(blocks_size))`.
-        // We are deviating from that by creating smaller buffers to fit just the data we will store in an output
-        // frame or reference frame buffer.
         if (uv) {
             return {
-                y_size_to_uv_size(color_config.subsampling_y, size().width()),
-                y_size_to_uv_size(color_config.subsampling_y, size().height()),
+                y_size_to_uv_size(color_config.subsampling_y, blocks_to_pixels(columns())),
+                y_size_to_uv_size(color_config.subsampling_y, blocks_to_pixels(rows())),
             };
         }
-        return size();
+        return {
+            blocks_to_pixels(columns()),
+            blocks_to_pixels(rows()),
+        };
     }
 
     Vector2D<FrameBlockContext> const& block_contexts() const { return m_block_contexts; }