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diff --git a/dom/canvas/test/webgl-conf/checkout/conformance2/rendering/instanced-rendering-large-divisor.html b/dom/canvas/test/webgl-conf/checkout/conformance2/rendering/instanced-rendering-large-divisor.html
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@@ -0,0 +1,145 @@
+<!--
+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 Instanced Arrays Conformance Tests - large vertex attrib divisors</title>
+<link rel="stylesheet" href="../../resources/js-test-style.css"/>
+<script src="../../js/desktop-gl-constants.js"></script>
+<script src="../../js/js-test-pre.js"></script>
+<script src="../../js/webgl-test-utils.js"></script>
+</head>
+<body>
+<div id="description"></div>
+<canvas id="canvas"> </canvas>
+<div id="console"></div>
+<script id="outputVertexShader" type="x-shader/x-vertex">#version 300 es
+layout(location = 0) in vec2 a_position;
+layout(location = 1) in float a_positionOffset;
+layout(location = 2) in vec4 a_color;
+out vec4 v_color;
+void main()
+{
+    gl_Position = vec4(a_position.x * 0.05 + a_positionOffset, a_position.y * 0.05, 0.0, 1.0);
+    v_color = a_color;
+}
+</script>
+
+<script id="outputFragmentShader" type="x-shader/x-fragment">#version 300 es
+precision highp float;
+in vec4 v_color;
+out vec4 my_FragColor;
+void main()
+{
+    my_FragColor = v_color;
+}
+</script>
+
+<script>
+"use strict";
+description("Test switching vertex attrib divisor of one attribute between different large values");
+// This is a regression test for http://anglebug.com/2832
+
+debug("");
+
+var wtu = WebGLTestUtils;
+var canvas = document.getElementById("canvas");
+canvas.width = 256;
+canvas.height = 256;
+var gl = wtu.create3DContext(canvas, null, 2);
+
+var colorDivisor = 65536 * 2;
+
+if (!gl) {
+    testFailed("WebGL context does not exist");
+} else {
+    testPassed("WebGL context exists");
+
+    runTest();
+}
+
+function runTest() {
+    var program = wtu.setupProgram(gl, ["outputVertexShader", "outputFragmentShader"]);
+
+    gl.clearColor(0.0, 0.0, 1.0, 1.0);
+
+    wtu.setupIndexedQuadWithOptions(gl, {positionLocation: 0});
+
+    var offsetBuf = gl.createBuffer();
+    gl.bindBuffer(gl.ARRAY_BUFFER, offsetBuf);
+    // Note that only the first two offsets below should be used for rendering.
+    // We add some extra ones to the buffer since it can reveal if a too small divisor is used on the WebGL backend.
+    var offsetData = [];
+    for (var i = 0; i < 4; ++i) {
+        offsetData.push(0.0 + i * 0.25);
+    }
+    gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(offsetData), gl.DYNAMIC_DRAW);
+
+    gl.enableVertexAttribArray(1);
+    gl.vertexAttribPointer(1, 1, gl.FLOAT, false, 0, 0);
+
+    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Setting up vertex buffer should succeed");
+
+    var colorBuf = gl.createBuffer();
+    gl.bindBuffer(gl.ARRAY_BUFFER, colorBuf);
+    // Red and green colors.
+    var colorData = new Float32Array([1.0, 0.0, 0.0, 1.0,
+                                      0.0, 1.0, 0.0, 1.0]);
+    gl.bufferData(gl.ARRAY_BUFFER, colorData, gl.DYNAMIC_DRAW);
+
+    gl.enableVertexAttribArray(2);
+    gl.vertexAttribPointer(2, 4, gl.FLOAT, false, 0, 0);
+    gl.vertexAttribDivisor(2, colorDivisor);
+
+    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Setting up color buffer should succeed");
+
+    var divisorsToTry = [
+        256,
+        65536,
+        65536 * 2
+    ];
+
+    for (var i = 0; i < divisorsToTry.length; ++i) {
+        runDrawElementsTest(divisorsToTry[i]);
+    }
+}
+
+function runDrawElementsTest(divisor) {
+    debug("Using divisor " + divisor);
+    gl.clear(gl.COLOR_BUFFER_BIT);
+    gl.vertexAttribDivisor(1, divisor);
+
+    var instanceCount = divisor + 1;
+    var quadsRendered = Math.floor((instanceCount - 1) / divisor) + 1;
+
+    gl.drawElementsInstanced(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0, instanceCount);
+
+    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Instanced draw should succeed");
+
+    for (var quadIndex = 0; quadIndex < quadsRendered + 1; ++quadIndex) {
+        var quadX = Math.floor((quadIndex / 8) * 256 + 128);
+        var quadY = 128;
+        if (quadIndex < quadsRendered) {
+            var quadColorIndex = Math.floor((quadIndex * divisor) / colorDivisor);
+            if (quadColorIndex == 0) {
+                wtu.checkCanvasRect(gl, quadX, quadY, 1, 1, [255, 0, 0, 255]);
+            } else {
+                wtu.checkCanvasRect(gl, quadX, quadY, 1, 1, [0, 255, 0, 255]);
+            }
+        } else {
+            wtu.checkCanvasRect(gl, quadX, quadY, 1, 1, [0, 0, 255, 255]);
+        }
+    }
+}
+
+debug("");
+var successfullyParsed = true;
+</script>
+<script src="../../js/js-test-post.js"></script>
+</body>
+</html>