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diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/manual/canvas-clear-on-zero-count-draw.html b/dom/canvas/test/webgl-conf/checkout/conformance/manual/canvas-clear-on-zero-count-draw.html
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+++ b/dom/canvas/test/webgl-conf/checkout/conformance/manual/canvas-clear-on-zero-count-draw.html
@@ -0,0 +1,90 @@
+<!--
+Copyright (c) 2019 The Khronos Group Inc.
+Use of this source code is governed by an MIT-style license that can be
+found in the LICENSE.txt file.
+-->
+
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8">
+<title>Check that the canvas is NOT recomposited after unsucessful draw call</title>
+<link rel="stylesheet" href="../../resources/js-test-style.css"/>
+<script src="../../js/js-test-pre.js"></script>
+<script src="../../js/webgl-test-utils.js"></script>
+<style>
+canvas {
+    border: 1px solid black;
+}
+.correct {
+    border: 1px solid black;
+    background-color: #ffffff;
+}
+</style>
+</head>
+<body>
+<pre>
+This test must be run manually.
+
+This test tests that a canvas is cleared
+even when a draw call has a zero count.
+
+You should see three <span class="correct">white rectangles</span>
+with black outlines on success.
+</pre>
+<canvas id='c1'></canvas>
+<canvas id='c2'></canvas>
+<canvas id='c3'></canvas>
+<div id="console"></div>
+<script id="vshader" type="x-shader/x-vertex">
+void main() {
+  gl_Position = vec4(0,0,0,1);
+}
+</script>
+<script id="fshader" type="x-shader/x-fragment">
+precision mediump float;
+void main() {
+  discard;
+}
+</script>
+<script>
+"use strict";
+var wtu = WebGLTestUtils;
+var c1 = document.getElementById("c1");
+var c2 = document.getElementById("c2");
+var c3 = document.getElementById("c2");
+var gl1 = wtu.create3DContext(c1);
+var gl2 = wtu.create3DContext(c2);
+var gl3 = wtu.create3DContext(c2);
+gl1.clearColor(0,1,0,1);
+gl1.clear(gl1.COLOR_BUFFER_BIT);
+gl2.clearColor(0,1,0,1);
+gl2.clear(gl2.COLOR_BUFFER_BIT);
+gl3.clearColor(0,1,0,1);
+gl3.clear(gl2.COLOR_BUFFER_BIT);
+
+wtu.waitForComposite(function() {
+  // test drawArrays
+  gl1.drawArrays(gl1.TRIANGLES, 0, 0);
+  wtu.glErrorShouldBe(gl1, gl1.NO_ERROR, "no errors");
+});
+
+wtu.waitForComposite(function() {
+  // test drawElements
+  var buf = gl2.createBuffer();
+  gl2.bindBuffer(gl2.ELEMENT_ARRAY_BUFFER, buf);
+  gl2.bufferData(gl2.ELEMENT_ARRAY_BUFFER, new Uint8Array(1), gl2.STATIC_DRAW);
+  gl2.drawElements(gl2.TRIANGLES, 0, gl2.UNSIGNED_SHORT, 0);
+  wtu.glErrorShouldBe(gl2, gl2.NO_ERROR, "no errors");
+});
+
+wtu.waitForComposite(function() {
+  // test draw with program.
+  wtu.setupProgram(gl3, ["vshader", "fshader"]);
+  gl1.drawArrays(gl3.TRIANGLES, 0, 0);
+  wtu.glErrorShouldBe(gl3, gl2.NO_ERROR, "no errors");
+});
+
+</script>
+</body>
+</html>