diff --git a/testing/web-platform/tests/media-capabilities/decodingInfo.any.js b/testing/web-platform/tests/media-capabilities/decodingInfo.any.js
index 061a226e3f67..7362c11f932c 100644
--- a/testing/web-platform/tests/media-capabilities/decodingInfo.any.js
+++ b/testing/web-platform/tests/media-capabilities/decodingInfo.any.js
@@ -3,7 +3,7 @@
 
 // Minimal VideoConfiguration that will be allowed per spec. All optional
 // properties are missing.
-var minimalVideoConfiguration = {
+const minimalVideoConfiguration = {
   contentType: 'video/webm; codecs="vp09.00.10.08"',
   width: 800,
   height: 600,
@@ -13,28 +13,29 @@ var minimalVideoConfiguration = {
 
 // Minimal AudioConfiguration that will be allowed per spec. All optional
 // properties are missing.
-var minimalAudioConfiguration = {
+const minimalAudioConfiguration = {
   contentType: 'audio/webm; codecs="opus"',
 };
 
 // AudioConfiguration with optional spatialRendering param.
-var audioConfigurationWithSpatialRendering = {
+const audioConfigurationWithSpatialRendering = {
   contentType: 'audio/webm; codecs="opus"',
   spatialRendering: true,
 };
 
 // VideoConfiguration with optional hdrMetadataType, colorGamut, and
 // transferFunction properties.
-var videoConfigurationWithDynamicRange = {
-  contentType: 'video/webm; codecs="vp09.00.10.08"',
+const videoConfigurationWithDynamicRange = {
+  contentType: 'video/webm; codecs="vp09.00.10.08.00.09.16.09.00"',
   width: 800,
   height: 600,
   bitrate: 3000,
   framerate: 24,
-  hdrMetadataType: "smpteSt2086",
-  colorGamut: "srgb",
-  transferFunction: "srgb",
-}
+  hdrMetadataType: 'smpteSt2086',
+  colorGamut: 'rec2020',
+  transferFunction: 'pq',
+};
+
 
 promise_test(t => {
   return promise_rejects_js(t, TypeError, navigator.mediaCapabilities.decodingInfo());
@@ -363,6 +364,25 @@ promise_test(t => {
   });
 }, "Test that decodingInfo with hdrMetadataType, colorGamut, and transferFunction set returns a valid MediaCapabilitiesInfo objects");
 
+promise_test(t => {
+  // VP9 has a default color space of BT.709 in the codec string. So this will
+  // mismatch against the provided colorGamut and transferFunction.
+  let bt709Config = videoConfigurationWithDynamicRange;
+  bt709Config.contentType = 'video/webm; codecs="vp09.00.10.08"';
+  return navigator.mediaCapabilities
+      .decodingInfo({
+        type: 'file',
+        video: bt709Config,
+      })
+      .then(ability => {
+        assert_equals(typeof ability.supported, 'boolean');
+        assert_equals(typeof ability.smooth, 'boolean');
+        assert_equals(typeof ability.powerEfficient, 'boolean');
+        assert_equals(typeof ability.keySystemAccess, 'object');
+        assert_false(ability.supported);
+      });
+}, 'Test that decodingInfo with mismatched codec color space is unsupported');
+
 promise_test(t => {
   return promise_rejects_js(t, TypeError, navigator.mediaCapabilities.decodingInfo({
     type: 'file',