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diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-audioworklet-interface/audioworkletnode-channel-count.https.html b/testing/web-platform/tests/webaudio/the-audio-api/the-audioworklet-interface/audioworkletnode-channel-count.https.html
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+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audioworklet-interface/audioworkletnode-channel-count.https.html
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+<!DOCTYPE html>
+<html>
+  <head>
+    <title>
+      Test AudioWorkletNode's dynamic channel count feature
+    </title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="/webaudio/resources/audit.js"></script>
+    <script src="/webaudio/resources/audit-util.js"></script>
+  </head>
+  <body>
+    <script id="layout-test-code">
+      let audit = Audit.createTaskRunner();
+
+      // Arbitrary numbers used to align the test with render quantum boundary.
+      let sampleRate = RENDER_QUANTUM_FRAMES * 100;
+      let renderLength = RENDER_QUANTUM_FRAMES * 2;
+      let context;
+
+      let filePath = 'processors/gain-processor.js';
+
+      let testChannelValues = [1, 2, 3];
+
+      // Creates a 3-channel buffer and play with BufferSourceNode. The source
+      // goes through a bypass AudioWorkletNode (gain value of 1).
+      audit.define('setup-buffer-and-worklet', (task, should) => {
+        context = new OfflineAudioContext(testChannelValues.length,
+                                          renderLength,
+                                          sampleRate);
+
+        // Explicitly sets the destination channelCountMode and
+        // channelInterpretation to make sure the result does no mixing.
+        context.channeCountMode = 'explicit';
+        context.channelInterpretation = 'discrete';
+
+        context.audioWorklet.addModule(filePath).then(() => {
+          let testBuffer = createConstantBuffer(context, 1, testChannelValues);
+          let sourceNode = new AudioBufferSourceNode(context);
+          let gainWorkletNode = new AudioWorkletNode(context, 'gain');
+
+          gainWorkletNode.parameters.get('gain').value = 1.0;
+          sourceNode.connect(gainWorkletNode).connect(context.destination);
+
+          // Suspend the context at 128 sample frames and play the source with
+          // the assigned buffer.
+          context.suspend(RENDER_QUANTUM_FRAMES/sampleRate).then(() => {
+            sourceNode.buffer = testBuffer;
+            sourceNode.loop = true;
+            sourceNode.start();
+            context.resume();
+          });
+          task.done();
+        });
+      });
+
+      // Verifies if the rendered buffer has all zero for the first half (before
+      // 128 samples) and the expected values for the second half.
+      audit.define('verify-rendered-buffer', (task, should) => {
+          context.startRendering().then(renderedBuffer => {
+            testChannelValues.forEach((value, index) => {
+              let channelData = renderedBuffer.getChannelData(index);
+              should(channelData.subarray(0, RENDER_QUANTUM_FRAMES),
+                     'First half of Channel #' + index)
+                  .beConstantValueOf(0);
+              should(channelData.subarray(RENDER_QUANTUM_FRAMES, renderLength),
+                     'Second half of Channel #' + index)
+                  .beConstantValueOf(value);
+            });
+            task.done();
+          });
+        });
+
+      audit.run();
+    </script>
+  </body>
+</html>