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diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/rendering/culling.html b/dom/canvas/test/webgl-conf/checkout/conformance/rendering/culling.html
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index 0000000000..74321f5cdd
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@@ -0,0 +1,127 @@
+<!--
+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">
+<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>
+<script id="vshader" type="x-shader/x-vertex">
+attribute vec2 pos;
+
+void main()
+{
+    gl_Position = vec4(pos, 0, 1);
+}
+</script>
+
+<script id="fshader" type="x-shader/x-fragment">
+precision mediump float;
+uniform vec4 col;
+
+void main()
+{
+    gl_FragColor = col;
+}
+</script>
+
+<script>
+"use strict";
+var wtu = WebGLTestUtils;
+
+function draw(gl, arr, colLoc, col) {
+    var vertices = new Float32Array(arr);
+    var vertBuf = gl.createBuffer();
+    gl.bindBuffer(gl.ARRAY_BUFFER, vertBuf);
+    gl.bufferData(gl.ARRAY_BUFFER, vertices, gl.STATIC_DRAW);
+    gl.vertexAttribPointer(0, 2, gl.FLOAT, false, 0, 0);
+    gl.uniform4fv(colLoc, col);
+    gl.drawArrays(gl.TRIANGLE_STRIP, 0, vertices.length / 2);
+}
+
+function clear(gl, col) {
+    gl.clearColor(col[0], col[1], col[2], col[3]);
+    gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
+}
+
+function check(gl, winding, shoulddraw) {
+    var msg = winding + ' face was ' + (shoulddraw ? '' : 'not ') + 'drawn.';
+    wtu.checkCanvasRect(gl, 0, 0, 1, 1, [0, 255, 0, 255], msg);
+}
+
+function runTest() {
+    var cwVertices = [-1, -1, -1, 1, 1, -1, 1, 1];
+    var ccwVertices = [-1, 1, -1, -1, 1, 1, 1, -1];
+    var red = [1, 0, 0, 1];
+    var green = [0, 1, 0, 1];
+    var ok;
+
+    var gl = wtu.create3DContext('testbed', { antialias: false });
+    if (!gl) {
+        testFailed('could not create context');
+        return;
+    }
+    var program = wtu.setupProgram(gl, ['vshader', 'fshader'], ['pos']);
+    var colLoc = gl.getUniformLocation(program, 'col');
+
+    gl.enableVertexAttribArray(0);
+
+    debug('CULL_FACE should be off by default');
+    clear(gl, red);
+    draw(gl, ccwVertices, colLoc, green);
+    check(gl, 'CCW', true);
+    clear(gl, red);
+    draw(gl, cwVertices, colLoc, green);
+    check(gl, 'CW', true);
+
+    debug('Enabling CULL_FACE');
+    gl.enable(gl.CULL_FACE);
+
+    debug('BACK and CCW should be set by default');
+    clear(gl, red);
+    draw(gl, ccwVertices, colLoc, green);
+    check(gl, 'CCW', true);
+    clear(gl, green);
+    draw(gl, cwVertices, colLoc, red);
+    check(gl, 'CW', false);
+
+    var tests = [{ cullFace : 'BACK', frontFace : 'CCW', drawCCW : true, drawCW : false},
+                 { cullFace : 'BACK', frontFace : 'CW', drawCCW : false, drawCW : true},
+                 { cullFace : 'FRONT', frontFace : 'CCW', drawCCW : false, drawCW : true },
+                 { cullFace : 'FRONT', frontFace : 'CW', drawCCW : true, drawCW : false},
+                 { cullFace : 'FRONT_AND_BACK', frontFace : 'CCW', drawCCW : false, drawCW : false},
+                 { cullFace : 'FRONT_AND_BACK', frontFace : 'CW', drawCCW : false, drawCW : false}];
+
+    for (var i = 0; i < tests.length; ++i) {
+        var t = tests[i];
+        debug('Setting ' + t.cullFace + ' and ' + t.frontFace);
+        gl.cullFace(gl[t.cullFace]);
+        gl.frontFace(gl[t.frontFace]);
+        clear(gl, t.drawCCW ? red : green);
+        draw(gl, ccwVertices, colLoc, t.drawCCW ? green : red);
+        check(gl, 'CCW', t.drawCCW);
+        clear(gl, t.drawCW ? red : green);
+        draw(gl, cwVertices, colLoc, t.drawCW ? green : red);
+        check(gl, 'CW', t.drawCW);
+    }
+}
+</script>
+</head>
+<body>
+<canvas id="testbed" width="16" height="16" style="width:50px; height:50px"></canvas>
+<div id="description"></div>
+<div id="console"></div>
+<script>
+"use strict";
+description('Verify that culling works');
+runTest();
+var successfullyParsed = true;
+</script>
+<script src="../../js/js-test-post.js"></script>
+</body>
+</html>