diff --git a/content/canvas/test/webgl/conformance/glsl/matrices/00_test_list.txt b/content/canvas/test/webgl/conformance/glsl/matrices/00_test_list.txt
new file mode 100644
index 000000000000..196b782b3db0
--- /dev/null
+++ b/content/canvas/test/webgl/conformance/glsl/matrices/00_test_list.txt
@@ -0,0 +1,2 @@
+glsl-mat4-to-mat3.html
+
diff --git a/content/canvas/test/webgl/conformance/glsl/matrices/glsl-mat4-to-mat3.html b/content/canvas/test/webgl/conformance/glsl/matrices/glsl-mat4-to-mat3.html
new file mode 100644
index 000000000000..8510a08c7b51
--- /dev/null
+++ b/content/canvas/test/webgl/conformance/glsl/matrices/glsl-mat4-to-mat3.html
@@ -0,0 +1,70 @@
+<!--
+Copyright (c) 2011 The Chromium Authors. All rights reserved.
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+ -->
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8">
+  <title>GLSL mat4 to mat3 test</title>
+  <link rel="stylesheet" href="../../../resources/js-test-style.css"/>
+  <link rel="stylesheet" href="../../resources/glsl-feature-tests.css"/>
+  <script src="../../../resources/js-test-pre.js"></script>
+  <script src="../../resources/webgl-test.js"> </script>
+  <script src="../../resources/webgl-test-utils.js"> </script>
+  <script src="../../resources/glsl-generator.js"> </script>
+</head>
+<body>
+<div id="description"></div>
+<div id="console"></div>
+<script id="shader_emu" type="something-not-js">
+mat3 mat3_emu(mat4 m4) {
+  return mat3(
+      m4[0][0], m4[0][1], m4[0][2],
+      m4[1][0], m4[1][1], m4[1][2],
+      m4[2][0], m4[2][1], m4[2][2]);
+}
+</script>
+<script id="shader_test" type="something-not-js">
+  mat4 m4 = mat4($(input), $(input).yzwx, $(input).zwxy, $(input).wxyz);
+  mat3 m3 = $(conversion)(m4);
+  vec3 c;
+  if ($(input).y < 0.33) {
+    c = m3[0];
+  } else if ($(input).y > 0.66) {
+    c = m3[1];
+  } else {
+    c = m3[2];
+  }
+  $(output) = vec4(c, 1);
+</script>
+<script>
+// See resources glsl-generator runBasicTest for how this works
+var wtu = WebGLTestUtils;
+GLSLGenerator.runBasicTest({
+  gridRes: 8,
+  tests: [
+    {
+      name: "mat4 to mat3",
+      reference: {
+        shader: wtu.getScript("shader_test"),
+        subs: {
+          emu: wtu.getScript("shader_emu"),
+          conversion: "mat3_emu"
+        }
+      },
+      test: {
+        shader: wtu.getScript("shader_test"),
+        subs: {
+          conversion: "mat3"
+        },
+      }
+    }
+  ]
+});
+successfullyParsed = true;
+</script>
+</body>
+</html>
+
diff --git a/content/canvas/test/webgl/conformance/misc/00_test_list.txt b/content/canvas/test/webgl/conformance/misc/00_test_list.txt
index d7b6b17cc1ed..cdc1f25a060d 100644
--- a/content/canvas/test/webgl/conformance/misc/00_test_list.txt
+++ b/content/canvas/test/webgl/conformance/misc/00_test_list.txt
@@ -5,7 +5,7 @@ invalid-passed-params.html
 is-object.html
 null-object-behaviour.html
 object-deletion-behaviour.html
-#shader-precision-format.html
+shader-precision-format.html
 type-conversion-test.html
 uninitialized-test.html
 webgl-specific.html
diff --git a/content/canvas/test/webgl/conformance/misc/shader-precision-format.html b/content/canvas/test/webgl/conformance/misc/shader-precision-format.html
new file mode 100644
index 000000000000..8cb675b3f2ab
--- /dev/null
+++ b/content/canvas/test/webgl/conformance/misc/shader-precision-format.html
@@ -0,0 +1,83 @@
+<!--
+Copyright (c) 2011 Mozilla Foundation. All rights reserved.
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+ -->
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8">
+<title>WebGL shader precision format test.</title>
+<link rel="stylesheet" href="../../resources/js-test-style.css"/>
+<script src="../../resources/js-test-pre.js"></script>
+<script src="../resources/webgl-test.js"> </script>
+<script src="../resources/webgl-test-utils.js"> </script>
+</head>
+<body>
+<canvas id="canvas" width="2" height="2" style="width: 40px; height: 40px;"></canvas>
+<div id="description"></div>
+<div id="console"></div>
+<script>
+var wtu = WebGLTestUtils;
+description(document.title);
+debug("Tests that WebGLShaderPrecisionFormat class and getShaderPrecisionFormat work.");
+debug("");
+var gl = create3DContext(document.getElementById("canvas"));
+
+function verifyShaderPrecisionFormat(shadertype, precisiontype) {
+    shouldBeTrue('gl.getShaderPrecisionFormat(' + shadertype + ', ' +
+                 precisiontype + ') instanceof WebGLShaderPrecisionFormat');
+}
+
+if (gl.getShaderPrecisionFormat == null || typeof gl.getShaderPrecisionFormat != 'function') {
+    debug("getShaderPrecisionFormat() function not found.");
+} else {
+    debug("");
+    debug("Test that getShaderPrecisionFormat returns a WebGLShaderPrecisionFormat object.");
+    debug("");
+
+    verifyShaderPrecisionFormat('gl.VERTEX_SHADER', 'gl.LOW_FLOAT');
+    verifyShaderPrecisionFormat('gl.VERTEX_SHADER', 'gl.MEDIUM_FLOAT');
+    verifyShaderPrecisionFormat('gl.VERTEX_SHADER', 'gl.HIGH_FLOAT');
+    verifyShaderPrecisionFormat('gl.VERTEX_SHADER', 'gl.LOW_INT');
+    verifyShaderPrecisionFormat('gl.VERTEX_SHADER', 'gl.MEDIUM_INT');
+    verifyShaderPrecisionFormat('gl.VERTEX_SHADER', 'gl.HIGH_INT');
+    verifyShaderPrecisionFormat('gl.FRAGMENT_SHADER', 'gl.LOW_FLOAT');
+    verifyShaderPrecisionFormat('gl.FRAGMENT_SHADER', 'gl.MEDIUM_FLOAT');
+    verifyShaderPrecisionFormat('gl.FRAGMENT_SHADER', 'gl.HIGH_FLOAT');
+    verifyShaderPrecisionFormat('gl.FRAGMENT_SHADER', 'gl.LOW_INT');
+    verifyShaderPrecisionFormat('gl.FRAGMENT_SHADER', 'gl.MEDIUM_INT');
+    verifyShaderPrecisionFormat('gl.FRAGMENT_SHADER', 'gl.HIGH_INT');
+
+    debug("");
+    debug("Test that getShaderPrecisionFormat throws an error with invalid parameters.");
+    debug("");
+
+    shouldGenerateGLError(gl, gl.INVALID_ENUM, 'gl.getShaderPrecisionFormat(gl.HIGH_INT, gl.VERTEX_SHADER)');
+
+    debug("");
+    debug("Test that WebGLShaderPrecisionFormat values are sensible.");
+    debug("");
+
+    var shaderPrecisionFormat = gl.getShaderPrecisionFormat(gl.VERTEX_SHADER, gl.LOW_FLOAT);
+    shouldBeTrue('shaderPrecisionFormat.rangeMin >= 0 && shaderPrecisionFormat.rangeMin <= 128');
+    shouldBeTrue('shaderPrecisionFormat.rangeMax >= 0 && shaderPrecisionFormat.rangeMax <= 128');
+    shouldBeTrue('shaderPrecisionFormat.precision >= 0 && shaderPrecisionFormat.precision <= 128');
+
+    debug("");
+    debug("Test that getShaderPrecisionFormat returns the same thing every call.");
+    debug("");
+
+    var shaderPrecisionFormat2 = gl.getShaderPrecisionFormat(gl.VERTEX_SHADER, gl.LOW_FLOAT);
+    shouldBeTrue('shaderPrecisionFormat.rangeMin == shaderPrecisionFormat2.rangeMin');
+    shouldBeTrue('shaderPrecisionFormat.rangeMax == shaderPrecisionFormat2.rangeMax');
+    shouldBeTrue('shaderPrecisionFormat.precision == shaderPrecisionFormat2.precision');
+}
+
+finishTest();
+</script>
+
+</body>
+</html>
+
+
