Merging upstream version 126.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 896 insertions, 5 deletions

diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/compressed-texture-utils.js b/dom/canvas/test/webgl-conf/checkout/js/tests/compressed-texture-utils.js
index 46d155f5f1..04396c9b32 100644
--- a/dom/canvas/test/webgl-conf/checkout/js/tests/compressed-texture-utils.js
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/compressed-texture-utils.js
@@ -67,6 +67,10 @@ let testCompressedFormatsUnavailableWhenExtensionDisabled = function(gl, compres
         if (compressedFormats.hasOwnProperty(name)) {
             gl.compressedTexImage2D(gl.TEXTURE_2D, 0, compressedFormats[name], testSize, testSize, 0, new Uint8Array(expectedByteLength(testSize, testSize, compressedFormats[name])));
             wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "Trying to use format " + name + " with extension disabled.");
+            if (gl.texStorage2D) {
+                gl.texStorage2D(gl.TEXTURE_2D, 1, compressedFormats[name], testSize, testSize);
+                wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "Trying to use format " + name + " with texStorage2D with extension disabled.");
+            }
         }
     }
     gl.bindTexture(gl.TEXTURE_2D, null);
@@ -255,4 +259,4 @@ return {
     testTexStorageLevelDimensions: testTexStorageLevelDimensions,
 };
 
-})();
\ No newline at end of file
+})();
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/drawingbuffer-storage-test.js b/dom/canvas/test/webgl-conf/checkout/js/tests/drawingbuffer-storage-test.js
new file mode 100644
index 0000000000..330171b320
--- /dev/null
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/drawingbuffer-storage-test.js
@@ -0,0 +1,275 @@
+/*
+Copyright (c) 2023 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.
+*/
+
+"use strict";
+
+let gl;
+let oldViewport;
+let width;
+let height;
+let format;
+let hasDrawingBufferStorage;
+let maxRenderbufferSize;
+
+function runTest(contextVersion) {
+  description();
+  debug("");
+
+  function initialize() {
+    let canvas = document.createElement("canvas");
+    gl = wtu.create3DContext(canvas, {antialias: false});
+    if (!gl) {
+      testFailed("context does not exist");
+      return [0, 0];
+    }
+
+    hasDrawingBufferStorage = `drawingBufferStorage` in gl;
+    if (!hasDrawingBufferStorage) {
+      testPassed("drawingBufferStorage not present -- skipping test");
+      return;
+    }
+
+    maxRenderbufferSize = gl.getParameter(gl.MAX_RENDERBUFFER_SIZE);
+  }
+
+  function testPixel(expected, actual, tol) {
+    let str = 'approx equal: expected: ' + expected + ', actual: ' + actual + ', tolerance: ' + tol;
+    for (let i = 0; i < 4; ++i) {
+      if (Math.abs(expected[i] - actual[i]) > tol) {
+        testFailed(str);
+        return;
+      }
+    }
+    testPassed(str);
+  }
+
+  function srgbToLinear(x) {
+    if (x < 0.0)
+      return 0.0;
+    if (x < 0.04045)
+      return x / 12.92;
+    if (x < 1.0) {
+      return Math.pow((x + 0.055)/1.044, 2.4);
+    }
+    return 1.0;
+  }
+
+  function testClearColor() {
+    // Make a fresh canvas.
+    let canvas = document.createElement("canvas");
+    canvas.width = 16;
+    canvas.height = 16;
+
+    gl = wtu.create3DContext(canvas, {antialias: false});
+    if (!gl) {
+      testFailed("context does not exist");
+      return;
+    }
+    testPassed("context exists");
+    shouldBe('gl.drawingBufferFormat', 'gl.RGBA8');
+
+    let testCase = function(f, size, clearColor, expectedPixel, tolerance) {
+      format = f;
+      width = size[0];
+      height = size[1];
+
+      gl.drawingBufferStorage(format, width, height);
+      shouldBe('gl.getError()', 'gl.NO_ERROR');
+
+      shouldBe('gl.drawingBufferFormat', 'format');
+      shouldBe('gl.drawingBufferWidth', 'width');
+      shouldBe('gl.drawingBufferHeight', 'height');
+
+      gl.clearColor(clearColor[0], clearColor[1], clearColor[2], clearColor[3]);
+      gl.clear(gl.COLOR_BUFFER_BIT);
+
+      let buf;
+      if (format == 0x881A /*RGBA16F*/) {
+        buf = new Float32Array(4);
+        gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.FLOAT, buf);
+      } else {
+        buf = new Uint8Array(4);
+        gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, buf);
+      }
+      testPixel(expectedPixel, buf, tolerance);
+    }
+
+    debug('Testing RGBA8');
+    testCase(gl.RGBA8, [16, 32],
+             [16 / 255, 32 / 255, 64 / 255, 128 / 255],
+             [16, 32, 64, 128],
+             0);
+
+    // WebGL 1 must use EXT_sRGB for SRGB8_ALPHA8.
+    let srgb8_alpha8 = gl.SRGB8_ALPHA8;
+    if (!srgb8_alpha8) {
+      let ext = gl.getExtension('EXT_sRGB');
+      if (ext) {
+        srgb8_alpha8 = ext.SRGB8_ALPHA8_EXT;
+      }
+    }
+    if (srgb8_alpha8) {
+      debug('Testing SRGB8_ALPHA8');
+      testCase(srgb8_alpha8, [16, 32],
+               [srgbToLinear(64/255), srgbToLinear(16/255), srgbToLinear(32/255), 128 / 255],
+               [64, 16, 32, 128],
+               1);
+    }
+
+    if (gl.getExtension('EXT_color_buffer_float')) {
+      // WebGL 1 must use EXT_color_buffer_half_float for RGBA16F.
+      let rgba16f = gl.RGBA16F;
+      if (!rgba16f) {
+        let ext = gl.getExtension('EXT_color_buffer_half_float');
+        if (ext) {
+          rgba16f = ext.RGBA16F_EXT;
+        }
+      }
+
+      debug('Testing RGBA16F');
+      testCase(rgba16f, [18, 28],
+               [0.25, 0.5, 0.75, 0.125],
+               [0.25, 0.5, 0.75, 0.125],
+               0.00001);
+    } else {
+      debug('Skipping RGBA16F');
+    }
+
+    shouldBe('gl.getError()', 'gl.NO_ERROR');
+  }
+
+  function testNoAlpha() {
+    let canvas = document.createElement("canvas");
+    canvas.width = 16;
+    canvas.height = 16;
+    gl = wtu.create3DContext(canvas, {alpha:false});
+    if (!gl) {
+      testFailed("context does not exist");
+      return;
+    }
+    debug('Testing alpha:false');
+
+    // Report RGB8 for the format.
+    shouldBe('gl.drawingBufferFormat', 'gl.RGB8');
+
+    // If WebGLContextAttributes.alpha is false, generate INVALID_OPERATION.
+    gl.drawingBufferStorage(gl.RGBA8, 16, 16);
+    shouldBe('gl.getError()', 'gl.INVALID_OPERATION');
+  }
+
+  function testMissingExtension() {
+    let canvas = document.createElement("canvas");
+    canvas.width = 16;
+    canvas.height = 16;
+    gl = wtu.create3DContext(canvas);
+    if (!gl) {
+      testFailed("context does not exist");
+      return;
+    }
+
+    debug('Testing use of RGBA16F without enabling EXT_color_buffer_float');
+    gl.drawingBufferStorage(gl.RGBA16F, 16, 16);
+    shouldBe('gl.getError()', 'gl.INVALID_ENUM');
+  }
+
+  function testMaxSize() {
+    let canvas = document.createElement("canvas");
+    canvas.width = 16;
+    canvas.height = 16;
+    gl = wtu.create3DContext(canvas);
+    if (!gl) {
+      testFailed("context does not exist");
+      return;
+    }
+
+    debug('Testing maximum size');
+    gl.drawingBufferStorage(gl.RGBA8, maxRenderbufferSize, maxRenderbufferSize);
+    shouldBe('gl.getError()', 'gl.NONE');
+    shouldBe('gl.drawingBufferWidth', 'maxRenderbufferSize');
+    shouldBe('gl.drawingBufferHeight', 'maxRenderbufferSize');
+
+    debug('Testing over-maximum width and ehgith');
+    gl.drawingBufferStorage(gl.RGBA8, maxRenderbufferSize+1, 16);
+    shouldBe('gl.getError()', 'gl.INVALID_VALUE');
+    gl.drawingBufferStorage(gl.RGBA8, 16, maxRenderbufferSize+1);
+    shouldBe('gl.getError()', 'gl.INVALID_VALUE');
+    shouldBe('gl.drawingBufferWidth', 'maxRenderbufferSize');
+    shouldBe('gl.drawingBufferHeight', 'maxRenderbufferSize');
+  }
+
+  function testDrawToCanvas() {
+    let canvasGL = document.createElement("canvas");
+    canvasGL.width = 16;
+    canvasGL.height = 16;
+    gl = wtu.create3DContext(canvasGL);
+    if (!gl) {
+      testFailed("context does not exist");
+      return;
+    }
+
+    let canvas2D = document.createElement("canvas");
+    canvas2D.width = 16;
+    canvas2D.height = 16;
+    let ctx = canvas2D.getContext('2d');
+    let imageData = new ImageData(16, 16);
+
+    let testCase = function(f, clearColor, canvasColor, tolerance) {
+      gl.drawingBufferStorage(f, 16, 16);
+      gl.clearColor(clearColor[0], clearColor[1], clearColor[2], clearColor[3]);
+      gl.clear(gl.COLOR_BUFFER_BIT);
+
+      ctx.putImageData(imageData, 0, 0);
+      ctx.drawImage(canvasGL, 0, 0);
+      testPixel(canvasColor, ctx.getImageData(8, 8, 1, 1).data, tolerance);
+    }
+
+    debug('Drawing RGBA to canvas');
+    testCase(gl.RGBA8, [16/255, 32/255, 64/255, 64/255], [64, 128, 255, 64], 0);
+
+    // WebGL 1 must use EXT_sRGB for SRGB8_ALPHA8.
+    let srgb8_alpha8 = gl.SRGB8_ALPHA8;
+    if (!srgb8_alpha8) {
+      let ext = gl.getExtension('EXT_sRGB');
+      if (ext) {
+        srgb8_alpha8 = ext.SRGB8_ALPHA8_EXT;
+      }
+    }
+    if (srgb8_alpha8) {
+      debug('Drawing opaque SRGB8_ALPHA8 to canvas');
+      testCase(srgb8_alpha8,
+               [srgbToLinear(64/255), srgbToLinear(32/255), srgbToLinear(16/255), 1.0],
+               [64, 32, 16, 255],
+               1);
+
+      debug('Drawing transparent SRGB8_ALPHA8 to canvas');
+      // We set the tolerance to 5 because of compounding error. The backbuffer
+      // may be off by 1, and then un-premultiplying alpha of 64/55 will multiply
+      // that error by 4. Then add one to be safe.
+      testCase(srgb8_alpha8,
+               [srgbToLinear(32/255), srgbToLinear(64/255), srgbToLinear(16/255), 64/255],
+               [128, 255, 64, 64],
+               5);
+    }
+
+    if (gl.getExtension('EXT_color_buffer_float')) {
+      debug('Drawing transparent RGBA16F to canvas');
+      testCase(gl.RGBA16F,
+               [32/255, 64/255, 16/255, 64/255],
+               [128, 255, 64, 64],
+               1);
+    }
+  }
+
+  let wtu = WebGLTestUtils;
+  initialize();
+  if (hasDrawingBufferStorage) {
+    testClearColor();
+    testNoAlpha();
+    testMissingExtension();
+    testMaxSize();
+    testDrawToCanvas();
+  }
+}
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/ext-color-buffer-half-float.js b/dom/canvas/test/webgl-conf/checkout/js/tests/ext-color-buffer-half-float.js
index 51509e8a6e..2975ec0fe4 100644
--- a/dom/canvas/test/webgl-conf/checkout/js/tests/ext-color-buffer-half-float.js
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/ext-color-buffer-half-float.js
@@ -422,6 +422,33 @@ if (!gl) {
       runRGB16FNegativeTest();
   }
 
+  if (version == 1) {
+      debug("");
+      debug("Testing that component type framebuffer attachment queries are rejected with the extension disabled");
+      const fbo = gl.createFramebuffer();
+      gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
+
+      const rbo = gl.createRenderbuffer();
+      gl.bindRenderbuffer(gl.RENDERBUFFER, rbo);
+      gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0,gl.RENDERBUFFER, rbo);
+      gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGB565, 8, 8);
+      wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Setup renderbuffer should succeed.");
+      shouldBeNull('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, 0x8211 /* FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE */)');
+      wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "Query must fail.");
+      gl.deleteRenderbuffer(rbo);
+
+      const tex = gl.createTexture();
+      gl.bindTexture(gl.TEXTURE_2D, tex);
+      gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0);
+      gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 8, 8, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
+      wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Setup texture should succeed.");
+      shouldBeNull('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, 0x8211 /* FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE */)');
+      wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "Query must fail.");
+      gl.deleteTexture(tex);
+
+      gl.deleteFramebuffer(fbo);
+  }
+
   let oesTextureHalfFloat = null;
   if (version == 1) {
     // oesTextureHalfFloat implicitly enables EXT_color_buffer_half_float if supported
@@ -466,6 +493,47 @@ if (!gl) {
       runCopyTexImageTest(true);
 
       runUniqueObjectTest();
+
+      {
+          debug("");
+          debug("Testing that component type framebuffer attachment queries are accepted with the extension enabled");
+          const fbo = gl.createFramebuffer();
+          gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
+
+          const rbo = gl.createRenderbuffer();
+          gl.bindRenderbuffer(gl.RENDERBUFFER, rbo);
+          gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0,gl.RENDERBUFFER, rbo);
+          gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGB565, 8, 8);
+          shouldBe('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT)', 'ext.UNSIGNED_NORMALIZED_EXT');
+          gl.renderbufferStorage(gl.RENDERBUFFER, ext.RGBA16F_EXT, 8, 8);
+          shouldBe('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT)', 'gl.FLOAT');
+          wtu.glErrorShouldBe(gl, gl.NO_ERROR, "No errors after valid renderbuffer attachment queries.");
+
+          gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT,gl.RENDERBUFFER, rbo);
+          gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_STENCIL, 8, 8);
+          wtu.glErrorShouldBe(gl, gl.NO_ERROR, "No errors after depth-stencil renderbuffer setup.");
+          shouldBeNull('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT, ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT)');
+          wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION, "Component type query is not allowed for combined depth-stencil attachments.");
+          gl.deleteRenderbuffer(rbo);
+
+          const tex = gl.createTexture();
+          gl.bindTexture(gl.TEXTURE_2D, tex);
+          gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0);
+          gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 8, 8, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
+          shouldBe('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT)', 'ext.UNSIGNED_NORMALIZED_EXT');
+          const tex_ext = gl.getExtension("OES_texture_half_float");
+          if (version > 1 || tex_ext) {
+              if (version > 1)
+                  gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA16F, 8, 8, 0, gl.RGBA, gl.HALF_FLOAT, null);
+              else
+                  gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 8, 8, 0, gl.RGBA, tex_ext.HALF_FLOAT_OES, null);
+              shouldBe('gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT)', 'gl.FLOAT');
+          }
+          wtu.glErrorShouldBe(gl, gl.NO_ERROR, "No errors after valid texture attachment queries.");
+          gl.deleteTexture(tex);
+
+          gl.deleteFramebuffer(fbo);
+      }
   }
 }
 
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-image-bitmap-from-video.js b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-image-bitmap-from-video.js
index 14cf4628be..504b70564e 100644
--- a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-image-bitmap-from-video.js
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-image-bitmap-from-video.js
@@ -14,7 +14,6 @@ function generateTest(internalFormat, pixelFormat, pixelType, prologue, resource
         { src: resourcePath + "red-green.mp4"           , type: 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"', },
         { src: resourcePath + "red-green.webmvp8.webm"  , type: 'video/webm; codecs="vp8, vorbis"',           },
         { src: resourcePath + "red-green.bt601.vp9.webm", type: 'video/webm; codecs="vp9"',                   },
-        { src: resourcePath + "red-green.theora.ogv"    , type: 'video/ogg; codecs="theora, vorbis"',         },
     ];
 
     function init()
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-video.js b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-video.js
index 6e8bcf96e9..8dadde2d69 100644
--- a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-video.js
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-2d-with-video.js
@@ -27,7 +27,6 @@ function generateTest(internalFormat, pixelFormat, pixelType, prologue, resource
       { src: resourcePath + "red-green.mp4"           , type: 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"', },
       { src: resourcePath + "red-green.webmvp8.webm"  , type: 'video/webm; codecs="vp8, vorbis"',           },
       { src: resourcePath + "red-green.bt601.vp9.webm", type: 'video/webm; codecs="vp9"',                   },
-      { src: resourcePath + "red-green.theora.ogv"    , type: 'video/ogg; codecs="theora, vorbis"',         },
     ];
 
     function init()
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-image-bitmap-from-video.js b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-image-bitmap-from-video.js
index a268f7d8d5..b1dbd33913 100644
--- a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-image-bitmap-from-video.js
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-image-bitmap-from-video.js
@@ -14,7 +14,6 @@ function generateTest(internalFormat, pixelFormat, pixelType, prologue, resource
         { src: resourcePath + "red-green.mp4"           , type: 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"', },
         { src: resourcePath + "red-green.webmvp8.webm"  , type: 'video/webm; codecs="vp8, vorbis"',           },
         { src: resourcePath + "red-green.bt601.vp9.webm", type: 'video/webm; codecs="vp9"',                   },
-        { src: resourcePath + "red-green.theora.ogv"    , type: 'video/ogg; codecs="theora, vorbis"',         },
     ];
 
     function init()
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-video.js b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-video.js
index 0c2c40e8a5..43ad660070 100644
--- a/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-video.js
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/tex-image-and-sub-image-3d-with-video.js
@@ -29,7 +29,6 @@ function generateTest(internalFormat, pixelFormat, pixelType, prologue, resource
       { src: resourcePath + "red-green.mp4"         , type: 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"', },
       { src: resourcePath + "red-green.bt601.vp9.webm", type: 'video/webm; codecs="vp9"',                   },
       { src: resourcePath + "red-green.webmvp8.webm", type: 'video/webm; codecs="vp8, vorbis"',           },
-      { src: resourcePath + "red-green.theora.ogv",   type: 'video/ogg; codecs="theora, vorbis"',         },
     ];
 
     function init()
diff --git a/dom/canvas/test/webgl-conf/checkout/js/tests/webgl-blend-func-extended.js b/dom/canvas/test/webgl-conf/checkout/js/tests/webgl-blend-func-extended.js
new file mode 100644
index 0000000000..086d9cfb16
--- /dev/null
+++ b/dom/canvas/test/webgl-conf/checkout/js/tests/webgl-blend-func-extended.js
@@ -0,0 +1,548 @@
+"use strict";
+description("This test verifies the functionality of the WEBGL_blend_func_extended extension, if it is available.");
+
+debug("");
+
+var wtu = WebGLTestUtils;
+var gl = wtu.create3DContext("c", undefined, contextVersion);
+var ext;
+
+function runTestNoExtension() {
+    debug("");
+    debug("Testing getParameter without the extension");
+    shouldBeNull("gl.getParameter(0x88FC /* MAX_DUAL_SOURCE_DRAW_BUFFERS_WEBGL */)");
+    wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "parameter unknown");
+    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+
+    if (contextVersion == 1) {
+        debug("");
+        debug("Testing SRC_ALPHA_SATURATE without the extension");
+
+        gl.blendFunc(gl.ONE, gl.SRC_ALPHA_SATURATE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "SRC_ALPHA_SATURATE not accepted as blendFunc dfactor");
+        gl.blendFuncSeparate(gl.ONE, gl.SRC_ALPHA_SATURATE, gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "SRC_ALPHA_SATURATE not accepted as blendFuncSeparate dstRGB");
+        gl.blendFuncSeparate(gl.ONE, gl.ONE, gl.ONE, gl.SRC_ALPHA_SATURATE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "SRC_ALPHA_SATURATE not accepted as blendFuncSeparate dstAlpha");
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+    }
+
+    debug("");
+    debug("Testing SRC1 blend funcs without the extension");
+
+    const extFuncs = {
+        SRC1_COLOR_WEBGL: 0x88F9,
+        SRC1_ALPHA_WEBGL: 0x8589,
+        ONE_MINUS_SRC1_COLOR_WEBGL: 0x88FA,
+        ONE_MINUS_SRC1_ALPHA_WEBGL: 0x88FB
+    };
+
+    for (const func in extFuncs) {
+        gl.blendFunc(extFuncs[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFunc sfactor`);
+        gl.blendFunc(gl.ONE, extFuncs[func]);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFunc dfactor`);
+        gl.blendFuncSeparate(extFuncs[func], gl.ONE, gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparate srcRGB`);
+        gl.blendFuncSeparate(gl.ONE, extFuncs[func], gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparate dstRGB`);
+        gl.blendFuncSeparate(gl.ONE, gl.ONE, extFuncs[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparate srcAlpha`);
+        gl.blendFuncSeparate(gl.ONE, gl.ONE, gl.ONE, extFuncs[func]);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparate dstAlpha`);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+    }
+
+    const dbi = gl.getExtension("OES_draw_buffers_indexed");
+    if (!dbi) return;
+
+    debug("");
+    debug("Testing indexed SRC1 blend funcs without the extension");
+    for (const func in extFuncs) {
+        dbi.blendFunciOES(0, extFuncs[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFunciOES src`);
+        dbi.blendFunciOES(0, gl.ONE, extFuncs[func]);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFunciOES dst`);
+        dbi.blendFuncSeparateiOES(0, extFuncs[func], gl.ONE, gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparateiOES srcRGB`);
+        dbi.blendFuncSeparateiOES(0, gl.ONE, extFuncs[func], gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparateiOES dstRGB`);
+        dbi.blendFuncSeparateiOES(0, gl.ONE, gl.ONE, extFuncs[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparateiOES srcAlpha`);
+        dbi.blendFuncSeparateiOES(0, gl.ONE, gl.ONE, gl.ONE, extFuncs[func]);
+        wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, `${func} not accepted as blendFuncSeparateiOES dstAlpha`);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+    }
+}
+
+function runEnumTests() {
+    debug("");
+    debug("Testing enums");
+    shouldBe("ext.SRC1_COLOR_WEBGL", "0x88F9");
+    shouldBe("ext.SRC1_ALPHA_WEBGL", "0x8589");
+    shouldBe("ext.ONE_MINUS_SRC1_COLOR_WEBGL", "0x88FA");
+    shouldBe("ext.ONE_MINUS_SRC1_ALPHA_WEBGL", "0x88FB");
+    shouldBe("ext.MAX_DUAL_SOURCE_DRAW_BUFFERS_WEBGL", "0x88FC");
+}
+
+function runQueryTests() {
+    debug("");
+    debug("Testing getParameter");
+    shouldBeGreaterThanOrEqual("gl.getParameter(ext.MAX_DUAL_SOURCE_DRAW_BUFFERS_WEBGL)", "1");
+    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+
+    if (contextVersion == 1) {
+        debug("");
+        debug("Testing SRC_ALPHA_SATURATE with the extension");
+
+        gl.blendFunc(gl.ONE, gl.SRC_ALPHA_SATURATE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "SRC_ALPHA_SATURATE accepted as blendFunc dfactor");
+        shouldBe("gl.getParameter(gl.BLEND_DST_RGB)", "gl.SRC_ALPHA_SATURATE");
+        shouldBe("gl.getParameter(gl.BLEND_DST_ALPHA)", "gl.SRC_ALPHA_SATURATE");
+        gl.blendFuncSeparate(gl.ONE, gl.SRC_ALPHA_SATURATE, gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "SRC_ALPHA_SATURATE accepted as blendFuncSeparate dstRGB");
+        shouldBe("gl.getParameter(gl.BLEND_DST_RGB)", "gl.SRC_ALPHA_SATURATE");
+        gl.blendFuncSeparate(gl.ONE, gl.ONE, gl.ONE, gl.SRC_ALPHA_SATURATE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "SRC_ALPHA_SATURATE accepted as blendFuncSeparate dstAlpha");
+        shouldBe("gl.getParameter(gl.BLEND_DST_ALPHA)", "gl.SRC_ALPHA_SATURATE");
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+    }
+
+    const extFuncs = [
+        "SRC1_COLOR_WEBGL",
+        "SRC1_ALPHA_WEBGL",
+        "ONE_MINUS_SRC1_COLOR_WEBGL",
+        "ONE_MINUS_SRC1_ALPHA_WEBGL"
+    ];
+
+    debug("");
+    debug("Testing blend state updates with SRC1 blend funcs");
+    for (const func of extFuncs) {
+        gl.blendFunc(ext[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFunc sfactor`);
+        shouldBe("gl.getParameter(gl.BLEND_SRC_RGB)", `ext.${func}`);
+        shouldBe("gl.getParameter(gl.BLEND_SRC_ALPHA)", `ext.${func}`);
+        gl.blendFunc(gl.ONE, ext[func]);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFunc dfactor`);
+        shouldBe("gl.getParameter(gl.BLEND_DST_RGB)", `ext.${func}`);
+        shouldBe("gl.getParameter(gl.BLEND_DST_ALPHA)", `ext.${func}`);
+        gl.blendFuncSeparate(ext[func], gl.ONE, gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFuncSeparate srcRGB`);
+        shouldBe("gl.getParameter(gl.BLEND_SRC_RGB)", `ext.${func}`);
+        gl.blendFuncSeparate(gl.ONE, ext[func], gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFuncSeparate dstRGB`);
+        shouldBe("gl.getParameter(gl.BLEND_DST_RGB)", `ext.${func}`);
+        gl.blendFuncSeparate(gl.ONE, gl.ONE, ext[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFuncSeparate srcAlpha`);
+        shouldBe("gl.getParameter(gl.BLEND_SRC_ALPHA)", `ext.${func}`);
+        gl.blendFuncSeparate(gl.ONE, gl.ONE, gl.ONE, ext[func]);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFuncSeparate dstAlpha`);
+        shouldBe("gl.getParameter(gl.BLEND_DST_ALPHA)", `ext.${func}`);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+    }
+
+    const dbi = gl.getExtension("OES_draw_buffers_indexed");
+    if (!dbi) return;
+
+    debug("");
+    debug("Testing indexed blend state updates with SRC1 blend funcs");
+    for (const func of extFuncs) {
+        dbi.blendFunciOES(0, ext[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFunciOES src`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_SRC_RGB, 0)", `ext.${func}`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_SRC_ALPHA, 0)", `ext.${func}`);
+        dbi.blendFunciOES(0, gl.ONE, ext[func]);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} accepted as blendFunciOES dst`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_DST_RGB, 0)", `ext.${func}`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_DST_ALPHA, 0)", `ext.${func}`);
+        dbi.blendFuncSeparateiOES(0, ext[func], gl.ONE, gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} not accepted as blendFuncSeparateiOES srcRGB`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_SRC_RGB, 0)", `ext.${func}`);
+        dbi.blendFuncSeparateiOES(0, gl.ONE, ext[func], gl.ONE, gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} not accepted as blendFuncSeparateiOES dstRGB`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_DST_RGB, 0)", `ext.${func}`);
+        dbi.blendFuncSeparateiOES(0, gl.ONE, gl.ONE, ext[func], gl.ONE);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} not accepted as blendFuncSeparateiOES srcAlpha`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_SRC_ALPHA, 0)", `ext.${func}`);
+        dbi.blendFuncSeparateiOES(0, gl.ONE, gl.ONE, gl.ONE, ext[func]);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, `${func} not accepted as blendFuncSeparateiOES dstAlpha`);
+        shouldBe("gl.getIndexedParameter(gl.BLEND_DST_ALPHA, 0)", `ext.${func}`);
+        wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");
+    }
+}
+
+function runShaderTests(extensionEnabled) {
+    debug("");
+    debug("Testing various shader compiles with extension " + (extensionEnabled ? "enabled" : "disabled"));
+
+    const shaderSets = [];
+
+    const macro100 = `precision mediump float;
+        void main() {
+        #ifdef GL_EXT_blend_func_extended
+            gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+        #else
+            #error no GL_EXT_blend_func_extended;
+        #endif
+        }`;
+    const macro300 = `#version 300 es
+        out mediump vec4 my_FragColor;
+        void main() {
+        #ifdef GL_EXT_blend_func_extended
+            my_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+        #else
+            #error no GL_EXT_blend_func_extended;
+        #endif
+        }`;
+    shaderSets.push([wtu.simpleVertexShader, macro100]);
+    if (contextVersion == 2) {
+        shaderSets.push([wtu.simpleVertexShaderESSL300, macro300]);
+    }
+
+    for (const shaders of shaderSets) {
+        // Expect the macro shader to succeed ONLY if enabled
+        if (wtu.setupProgram(gl, shaders)) {
+            if (extensionEnabled) {
+                testPassed("Macro defined in shaders when extension is enabled");
+            } else {
+                testFailed("Macro defined in shaders when extension is disabled");
+            }
+        } else {
+            if (extensionEnabled) {
+                testFailed("Macro not defined in shaders when extension is enabled");
+            } else {
+                testPassed("Macro not defined in shaders when extension is disabled");
+            }
+        }
+    }
+
+    shaderSets.length = 0;
+
+    const missing100 = `
+        void main() {
+            gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+            gl_SecondaryFragColorEXT = vec4(0.0, 1.0, 0.0, 1.0);
+        }`;
+    shaderSets.push([wtu.simpleVertexShader, missing100]);
+
+    const missing300 = `#version 300 es
+        layout(location = 0)            out mediump vec4 oColor0;
+        layout(location = 0, index = 1) out mediump vec4 oColor1;
+        void main() {
+            oColor0 = vec4(1.0, 0.0, 0.0, 1.0);
+            oColor1 = vec4(0.0, 1.0, 0.0, 1.0);
+        }`;
+    if (contextVersion == 2) {
+        shaderSets.push([wtu.simpleVertexShaderESSL300, missing300]);
+    }
+
+    // Always expect the shader missing the #extension pragma to fail (whether enabled or not)
+    for (const shaders of shaderSets) {
+        if (wtu.setupProgram(gl, shaders)) {
+            testFailed("Secondary fragment output allowed without #extension pragma");
+        } else {
+            testPassed("Secondary fragment output disallowed without #extension pragma");
+        }
+    }
+
+    shaderSets.length = 0;
+
+    const valid100 = `#extension GL_EXT_blend_func_extended : enable
+        void main() {
+            gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+            gl_SecondaryFragColorEXT = vec4(0.0, 1.0, 0.0, 1.0);
+        }`;
+    shaderSets.push([wtu.simpleVertexShader, valid100]);
+
+    const valid300 = `#version 300 es
+        #extension GL_EXT_blend_func_extended : enable
+        layout(location = 0)            out mediump vec4 oColor0;
+        layout(location = 0, index = 1) out mediump vec4 oColor1;
+        void main() {
+            oColor0 = vec4(1.0, 0.0, 0.0, 1.0);
+            oColor1 = vec4(0.0, 1.0, 0.0, 1.0);
+        }`;
+    if (contextVersion == 2) {
+        shaderSets.push([wtu.simpleVertexShaderESSL300, valid300]);
+    }
+
+    // Try to compile a shader using a secondary fragment output that should only succeed if enabled
+    for (const shaders of shaderSets) {
+        if (wtu.setupProgram(gl, shaders)) {
+            if (extensionEnabled) {
+                testPassed("Secondary fragment output compiled successfully when extension enabled");
+            } else {
+                testFailed("Secondary fragment output compiled successfully when extension disabled");
+            }
+        } else {
+            if (extensionEnabled) {
+                testFailed("Secondary fragment output failed to compile when extension enabled");
+            } else {
+                testPassed("Secondary fragment output failed to compile when extension disabled");
+            }
+        }
+    }
+
+    // ESSL 3.00: Testing that multiple outputs require explicit locations
+    if (contextVersion == 2) {
+        const locations300 = `#version 300 es
+            #extension GL_EXT_blend_func_extended : enable
+            out mediump vec4 color0;
+            out mediump vec4 color1;
+            void main() {
+                color0 = vec4(1.0, 0.0, 0.0, 1.0);
+                color1 = vec4(0.0, 1.0, 0.0, 1.0);
+            }`;
+        if (wtu.setupProgram(gl, [wtu.simpleVertexShaderESSL300, locations300])) {
+            testFailed("Multiple fragment outputs compiled successfully without explicit locations");
+        } else {
+            testPassed("Multiple fragment outputs failed to compile without explicit locations");
+        }
+    }
+}
+
+function runMissingOutputsTests() {
+    debug("");
+    debug("Test draw calls with missing fragment outputs");
+
+    wtu.setupUnitQuad(gl);
+    gl.blendFunc(gl.ONE, ext.SRC1_COLOR_WEBGL);
+
+    for (const enabled of [false, true]) {
+        if (enabled) {
+            gl.enable(gl.BLEND);
+        } else {
+            gl.disable(gl.BLEND);
+        }
+
+        for (const maskedOut of [false, true]) {
+            gl.colorMask(!maskedOut, false, false, false);
+
+            const label = `Dual-source blending ${enabled ? "ENABLED" : "DISABLED"}, ` +
+                          `missing fragment outputs, and ` +
+                          `${maskedOut ? "" : "NOT "}all color channels masked out`;
+            debug(`ESSL 1.00: ${label}`);
+
+            {
+                const none = "void main() {}";
+                wtu.setupProgram(gl, [wtu.simpleVertexShader, none]);
+                wtu.drawUnitQuad(gl);
+                wtu.glErrorShouldBe(gl, maskedOut ? gl.NO_ERROR : gl.INVALID_OPERATION,
+                                    "no fragment outputs");
+            }
+
+            {
+                const fragColor = `
+                    void main() {
+                        gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+                    }`;
+                wtu.setupProgram(gl, [wtu.simpleVertexShader, fragColor]);
+                wtu.drawUnitQuad(gl);
+                wtu.glErrorShouldBe(gl, (!enabled || maskedOut) ? gl.NO_ERROR : gl.INVALID_OPERATION,
+                                    "only gl_FragColor");
+            }
+
+            {
+                const secondaryFragColor = `#extension GL_EXT_blend_func_extended : enable
+                    void main() {
+                        gl_SecondaryFragColorEXT = vec4(0.0, 1.0, 0.0, 1.0);
+                    }`;
+                wtu.setupProgram(gl, [wtu.simpleVertexShader, secondaryFragColor]);
+                wtu.drawUnitQuad(gl);
+                wtu.glErrorShouldBe(gl, maskedOut ? gl.NO_ERROR : gl.INVALID_OPERATION,
+                                    "only gl_SecondaryFragColorEXT");
+            }
+
+            if (contextVersion == 1) continue;
+
+            debug(`ESSL 3.00: ${label}`);
+
+            {
+                const none = `#version 300 es
+                    void main() {}`;
+                wtu.setupProgram(gl, [wtu.simpleVertexShaderESSL300, none]);
+                wtu.drawUnitQuad(gl);
+                wtu.glErrorShouldBe(gl, maskedOut ? gl.NO_ERROR : gl.INVALID_OPERATION,
+                                    "no fragment outputs");
+            }
+
+            {
+                const color0 = `#version 300 es
+                    out mediump vec4 color0;
+                    void main() {
+                        color0 = vec4(1.0, 0.0, 0.0, 1.0);
+                    }`;
+                wtu.setupProgram(gl, [wtu.simpleVertexShaderESSL300, color0]);
+                wtu.drawUnitQuad(gl);
+                wtu.glErrorShouldBe(gl, (!enabled || maskedOut) ? gl.NO_ERROR : gl.INVALID_OPERATION,
+                                    "only index 0 output");
+            }
+
+            {
+                const color1 = `#version 300 es
+                    #extension GL_EXT_blend_func_extended : enable
+                    layout(location = 0, index = 1) out mediump vec4 color1;
+                    void main() {
+                        color1 = vec4(0.0, 1.0, 0.0, 1.0);
+                    }`;
+                wtu.setupProgram(gl, [wtu.simpleVertexShaderESSL300, color1]);
+                wtu.drawUnitQuad(gl);
+                wtu.glErrorShouldBe(gl, maskedOut ? gl.NO_ERROR : gl.INVALID_OPERATION,
+                                    "only index 1 output");
+            }
+        }
+    }
+    gl.colorMask(true, true, true, true);
+}
+
+function runDrawBuffersLimitTests() {
+    const dbi = gl.getExtension("OES_draw_buffers_indexed");
+    if (!dbi) return;
+
+    debug("");
+    debug("Testing that dual-source blending limits the number of active draw buffers");
+
+    const rb0 = gl.createRenderbuffer();
+    gl.bindRenderbuffer(gl.RENDERBUFFER, rb0);
+    gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA8, 1, 1);
+
+    const rb1 = gl.createRenderbuffer();
+    gl.bindRenderbuffer(gl.RENDERBUFFER, rb1);
+    gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA8, 1, 1);
+
+    gl.bindRenderbuffer(gl.RENDERBUFFER, null);
+
+    const fbo = gl.createFramebuffer();
+    gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
+    gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.RENDERBUFFER, rb0);
+    gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT1, gl.RENDERBUFFER, rb1);
+    wtu.framebufferStatusShouldBe(gl, gl.FRAMEBUFFER, gl.FRAMEBUFFER_COMPLETE);
+
+    const fs = `#version 300 es
+        #extension GL_EXT_blend_func_extended : enable
+        layout(location = 0, index = 0) out mediump vec4 color0;
+        layout(location = 0, index = 1) out mediump vec4 color1;
+        void main() {
+            color0 = vec4(1.0, 0.0, 0.0, 1.0);
+            color1 = vec4(0.0, 1.0, 0.0, 1.0);
+        }`;
+    wtu.setupProgram(gl, [wtu.simpleVertexShaderESSL300, fs]);
+
+    wtu.setupUnitQuad(gl);
+
+    // Enable both draw buffers
+    gl.drawBuffers([gl.COLOR_ATTACHMENT0, gl.COLOR_ATTACHMENT1]);
+
+    // Mask out draw buffer 1 to pass missing fragment outputs check
+    dbi.colorMaskiOES(1, false, false, false, false);
+
+    const extFuncs = [
+        "SRC1_COLOR_WEBGL",
+        "SRC1_ALPHA_WEBGL",
+        "ONE_MINUS_SRC1_COLOR_WEBGL",
+        "ONE_MINUS_SRC1_ALPHA_WEBGL"
+    ];
+
+    for (const func of extFuncs) {
+        for (let slot = 0; slot < 4; slot++) {
+            let param;
+            switch (slot) {
+                case 0:
+                    param = "srcRGB";
+                    gl.blendFuncSeparate(ext[func], gl.ONE, gl.ONE, gl.ONE);
+                    break;
+                case 1:
+                    param = "dstRGB";
+                    gl.blendFuncSeparate(gl.ONE, ext[func], gl.ONE, gl.ONE);
+                    break;
+                case 2:
+                    param = "srcAlpha";
+                    gl.blendFuncSeparate(gl.ONE, gl.ONE, ext[func], gl.ONE);
+                    break;
+                case 3:
+                    param = "dstAlpha";
+                    gl.blendFuncSeparate(gl.ONE, gl.ONE, gl.ONE, ext[func]);
+                    break;
+            }
+            debug(`Testing ${func} with ${param}`);
+
+            // Limit must be applied even with blending disabled
+            gl.disable(gl.BLEND);
+            wtu.drawUnitQuad(gl);
+            wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION, "blending disabled");
+
+            gl.enable(gl.BLEND);
+            wtu.drawUnitQuad(gl);
+            wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION, "blending enabled");
+
+            // Limit is not applied when non-SRC1 funcs are used
+            gl.blendFunc(gl.ONE, gl.ONE);
+            wtu.drawUnitQuad(gl);
+            wtu.glErrorShouldBe(gl, gl.NO_ERROR, "dual-source blending disabled");
+        }
+    }
+    gl.bindFramebuffer(gl.FRAMEBUFFER, null);
+}
+
+function runBlendingTests() {
+    debug("");
+    debug("Testing rendering with two most common dual-source blending configurations");
+
+    const fs = `#extension GL_EXT_blend_func_extended : enable
+        uniform mediump vec4 u_src0;
+        uniform mediump vec4 u_src1;
+        void main() {
+            gl_FragColor             = u_src0;
+            gl_SecondaryFragColorEXT = u_src1;
+        }`;
+    const program = wtu.setupProgram(gl, [wtu.simpleVertexShader, fs]);
+    const uSrc0 = gl.getUniformLocation(program, "u_src0");
+    const uSrc1 = gl.getUniformLocation(program, "u_src1");
+
+    gl.enable(gl.BLEND);
+    wtu.setupUnitQuad(gl);
+    gl.clearColor(1.0, 1.0, 1.0, 1.0);
+
+    gl.clear(gl.COLOR_BUFFER_BIT);
+    gl.blendFunc(gl.ONE, ext.SRC1_COLOR_WEBGL);
+    gl.uniform4f(uSrc0, 0.250, 0.375, 0.500, 0.625);
+    gl.uniform4f(uSrc1, 0.125, 0.125, 0.125, 0.125);
+    wtu.drawUnitQuad(gl);
+    wtu.checkCanvas(gl, [96, 128, 159, 191], "Multiply destination by SRC1 and add SRC0", 2);
+
+    gl.clear(gl.COLOR_BUFFER_BIT);
+    gl.blendFunc(ext.SRC1_COLOR_WEBGL, ext.ONE_MINUS_SRC1_COLOR_WEBGL);
+    gl.uniform4f(uSrc0, 0.125, 0.125, 0.125, 0.125);
+    gl.uniform4f(uSrc1, 0.500, 0.375, 0.250, 0.125);
+    wtu.drawUnitQuad(gl);
+    wtu.checkCanvas(gl, [143, 171, 199, 227], "Per-channel color interpolation using SRC1", 2);
+}
+
+function runTest() {
+    if (!gl) {
+        testFailed("context does not exist");
+        return;
+    }
+    testPassed("context exists");
+
+    runTestNoExtension();
+    runShaderTests(false);
+
+    ext = gl.getExtension("WEBGL_blend_func_extended");
+    wtu.runExtensionSupportedTest(gl, "WEBGL_blend_func_extended", ext !== null);
+
+    if (ext !== null) {
+        runEnumTests();
+        runQueryTests();
+        runShaderTests(true);
+        runMissingOutputsTests();
+        runDrawBuffersLimitTests();
+        runBlendingTests();
+    } else {
+        testPassed("No WEBGL_blend_func_extended support -- this is legal");
+    }
+}
+
+runTest();
+
+var successfullyParsed = true;