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diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/attribs/gl-vertex-attrib-zero-issues.html b/dom/canvas/test/webgl-conf/checkout/conformance/attribs/gl-vertex-attrib-zero-issues.html
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+++ b/dom/canvas/test/webgl-conf/checkout/conformance/attribs/gl-vertex-attrib-zero-issues.html
@@ -0,0 +1,131 @@
+<!--
+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>WebGL Enable Vertex Attrib Zero Test</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>
+</head>
+<body>
+<canvas id="example" width="50" height="50">
+</canvas>
+<div id="description"></div>
+<div id="console"></div>
+<script id="vshader" type="x-shader/x-vertex">
+    attribute vec4 vPosition;
+    void main()
+    {
+        gl_Position = vPosition;
+    }
+</script>
+
+<script id="fshader" type="x-shader/x-fragment">
+    void main()
+    {
+        gl_FragColor = vec4(0.0,1.0,0.0,1.0);
+    }
+</script>
+
+<script>
+"use strict";
+description("Test some of the issues of the difference between attrib 0 on OpenGL vs WebGL");
+debug("");
+var wtu = WebGLTestUtils;
+var gl = wtu.create3DContext("example");
+var g_program;
+var g_attribLocation;
+function setup(attribIndex) {
+  var program = wtu.setupProgram(
+      gl, ['vshader', 'fshader'], ['vPosition'], [attribIndex]);
+  g_program = program;
+  g_attribLocation = attribIndex;
+  shouldBe("g_attribLocation", "gl.getAttribLocation(g_program, 'vPosition')");
+  return program;
+}
+
+function setupVerts(numVerts) {
+  var verts = [
+     1.0,  1.0, 0.0,
+    -1.0,  1.0, 0.0,
+    -1.0, -1.0, 0.0,
+     1.0,  1.0, 0.0,
+    -1.0, -1.0, 0.0,
+     1.0, -1.0, 0.0
+  ];
+  var positions = new Float32Array(numVerts * 3);
+  var indices = new Uint16Array(numVerts);
+  for (var ii = 0; ii < numVerts; ++ii) {
+    var ndx = ii % 6;
+    var dst = ii * 3;
+    var src = ndx * 3;
+    for (var jj = 0; jj < 3; ++jj) {
+      positions[dst + jj] = verts[src + jj];
+    }
+    indices[ii] = ii;
+  }
+  var vertexObject = gl.createBuffer();
+  gl.bindBuffer(gl.ARRAY_BUFFER, vertexObject);
+  gl.bufferData(gl.ARRAY_BUFFER, positions, gl.STATIC_DRAW);
+  var indexBuffer = gl.createBuffer();
+  gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, indexBuffer);
+  gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, indices, gl.STATIC_DRAW);
+}
+
+var p0 = setup(0);
+var p3 = setup(3);
+setupVerts(60000);
+
+for (var ii = 0; ii < 5; ++ii) {
+  // test drawing with attrib 0
+  gl.useProgram(p0);
+  gl.enableVertexAttribArray(0);
+  gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0);
+  gl.clear(gl.COLOR_BUFFER_BIT);
+  gl.drawElements(gl.TRIANGLES, 60000, gl.UNSIGNED_SHORT, 0);
+  wtu.glErrorShouldBe(
+      gl, gl.NO_ERROR,
+      "drawing using attrib 0 with 6 verts");
+  wtu.checkCanvas(gl, [0, 255, 0, 255], "canvas should be green");
+  gl.disableVertexAttribArray(0);
+
+  // test drawing without attrib 0
+  gl.useProgram(p3);
+  gl.enableVertexAttribArray(3);
+  gl.vertexAttribPointer(3, 3, gl.FLOAT, false, 0, 0);
+  gl.clear(gl.COLOR_BUFFER_BIT);
+  gl.drawArrays(gl.TRIANGLES, 0, 60000);
+  wtu.glErrorShouldBe(
+      gl, gl.NO_ERROR,
+      "drawing using attrib 3 with 60000 verts");
+  wtu.checkCanvas(gl, [0, 255, 0, 255], "canvas should be green");
+  gl.disableVertexAttribArray(3);
+
+  // This second test of drawing without attrib0 uncovered a bug in chrome
+  // where after the draw without attrib0 the attrib 0 emulation code disabled
+  // attrib 0 and it was never re-enabled so this next draw failed.
+  gl.useProgram(p3);
+  gl.enableVertexAttribArray(3);
+  gl.clear(gl.COLOR_BUFFER_BIT);
+  gl.drawElements(gl.TRIANGLES, 60000, gl.UNSIGNED_SHORT, 0);
+  wtu.glErrorShouldBe(
+      gl, gl.NO_ERROR,
+      "drawing using attrib 3 with 60000 verts");
+  wtu.checkCanvas(gl, [0, 255, 0, 255], "canvas should be green");
+  gl.disableVertexAttribArray(3);
+}
+
+
+var successfullyParsed = true;
+</script>
+<script src="../../js/js-test-post.js"></script>
+
+</body>
+</html>
+