--- a/dom/canvas/WebGLContext.h
+++ b/dom/canvas/WebGLContext.h
@@ -268,16 +268,17 @@ class WebGLContext
     , public WebGLRectangleObject
     , public nsWrapperCache
 {
     friend class ScopedDrawHelper;
     friend class ScopedDrawWithTransformFeedback;
     friend class ScopedFBRebinder;
     friend class WebGL2Context;
     friend class WebGLContextUserData;
+    friend class WebGLExtensionCompressedTextureASTC;
     friend class WebGLExtensionCompressedTextureATC;
     friend class WebGLExtensionCompressedTextureES3;
     friend class WebGLExtensionCompressedTextureETC1;
     friend class WebGLExtensionCompressedTexturePVRTC;
     friend class WebGLExtensionCompressedTextureS3TC;
     friend class WebGLExtensionDepthTexture;
     friend class WebGLExtensionDisjointTimerQuery;
     friend class WebGLExtensionDrawBuffers;

--- a/dom/canvas/WebGLContextExtensions.cpp
+++ b/dom/canvas/WebGLContextExtensions.cpp
@@ -43,16 +43,17 @@ WebGLContext::GetExtensionString(WebGLEx
         WEBGL_EXTENSION_IDENTIFIER(OES_element_index_uint)
         WEBGL_EXTENSION_IDENTIFIER(OES_standard_derivatives)
         WEBGL_EXTENSION_IDENTIFIER(OES_texture_float)
         WEBGL_EXTENSION_IDENTIFIER(OES_texture_float_linear)
         WEBGL_EXTENSION_IDENTIFIER(OES_texture_half_float)
         WEBGL_EXTENSION_IDENTIFIER(OES_texture_half_float_linear)
         WEBGL_EXTENSION_IDENTIFIER(OES_vertex_array_object)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_color_buffer_float)
+        WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_astc)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_atc)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_etc)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_etc1)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_pvrtc)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_s3tc)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_debug_renderer_info)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_debug_shaders)
         WEBGL_EXTENSION_IDENTIFIER(WEBGL_depth_texture)
@@ -117,16 +118,18 @@ WebGLContext::IsExtensionSupported(WebGL
     case WebGLExtensionID::EXT_texture_filter_anisotropic:
         return gl->IsExtensionSupported(gl::GLContext::EXT_texture_filter_anisotropic);
 
     // OES_
     case WebGLExtensionID::OES_texture_float_linear:
         return gl->IsSupported(gl::GLFeature::texture_float_linear);
 
     // WEBGL_
+    case WebGLExtensionID::WEBGL_compressed_texture_astc:
+        return WebGLExtensionCompressedTextureASTC::IsSupported(this);
     case WebGLExtensionID::WEBGL_compressed_texture_atc:
         return gl->IsExtensionSupported(gl::GLContext::AMD_compressed_ATC_texture);
     case WebGLExtensionID::WEBGL_compressed_texture_etc:
         return gl->IsSupported(gl::GLFeature::ES3_compatibility);
     case WebGLExtensionID::WEBGL_compressed_texture_etc1:
         return gl->IsExtensionSupported(gl::GLContext::OES_compressed_ETC1_RGB8_texture);
     case WebGLExtensionID::WEBGL_compressed_texture_pvrtc:
         return gl->IsExtensionSupported(gl::GLContext::IMG_texture_compression_pvrtc);
@@ -394,16 +397,19 @@ WebGLContext::EnableExtension(WebGLExten
     case WebGLExtensionID::OES_vertex_array_object:
         obj = new WebGLExtensionVertexArray(this);
         break;
 
     // WEBGL_
     case WebGLExtensionID::WEBGL_color_buffer_float:
         obj = new WebGLExtensionColorBufferFloat(this);
         break;
+    case WebGLExtensionID::WEBGL_compressed_texture_astc:
+        obj = new WebGLExtensionCompressedTextureASTC(this);
+        break;
     case WebGLExtensionID::WEBGL_compressed_texture_atc:
         obj = new WebGLExtensionCompressedTextureATC(this);
         break;
     case WebGLExtensionID::WEBGL_compressed_texture_etc:
         obj = new WebGLExtensionCompressedTextureES3(this);
         break;
     case WebGLExtensionID::WEBGL_compressed_texture_etc1:
         obj = new WebGLExtensionCompressedTextureETC1(this);

new file mode 100644
--- /dev/null
+++ b/dom/canvas/WebGLExtensionCompressedTextureASTC.cpp
@@ -0,0 +1,95 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "WebGLExtensions.h"
+
+#include "GLContext.h"
+#include "mozilla/dom/WebGLRenderingContextBinding.h"
+#include "WebGLContext.h"
+
+namespace mozilla {
+
+WebGLExtensionCompressedTextureASTC::WebGLExtensionCompressedTextureASTC(WebGLContext* webgl)
+    : WebGLExtensionBase(webgl)
+{
+    MOZ_ASSERT(IsSupported(webgl), "Don't construct extension if unsupported.");
+
+    RefPtr<WebGLContext> webgl_ = webgl; // Bug 1201275
+    const auto fnAdd = [&webgl_](GLenum sizedFormat, webgl::EffectiveFormat effFormat) {
+        auto& fua = webgl_->mFormatUsage;
+
+        auto usage = fua->EditUsage(effFormat);
+        usage->isFilterable = true;
+        fua->AllowSizedTexFormat(sizedFormat, usage);
+
+        webgl_->mCompressedTextureFormats.AppendElement(sizedFormat);
+    };
+
+#define FOO(x) LOCAL_GL_ ## x, webgl::EffectiveFormat::x
+
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_4x4_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_5x4_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_5x5_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_6x5_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_6x6_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_8x5_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_8x6_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_8x8_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_10x5_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_10x6_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_10x8_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_10x10_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_12x10_KHR));
+    fnAdd(FOO(COMPRESSED_RGBA_ASTC_12x12_KHR));
+
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR));
+    fnAdd(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR));
+
+#undef FOO
+}
+
+WebGLExtensionCompressedTextureASTC::~WebGLExtensionCompressedTextureASTC()
+{
+}
+
+void
+WebGLExtensionCompressedTextureASTC::GetSupportedProfiles(dom::Nullable< nsTArray<nsString> >& retval) const
+{
+    retval.SetNull();
+    if (mIsLost) {
+        mContext->ErrorInvalidOperation("%s: Extension is lost.",
+                                        "drawElementsInstancedANGLE");
+        return;
+    }
+
+    nsTArray<nsString>& arr = retval.SetValue();
+    arr.AppendElement(NS_LITERAL_STRING("ldr"));
+
+    if (mContext->gl->IsExtensionSupported(gl::GLContext::KHR_texture_compression_astc_hdr)) {
+        arr.AppendElement(NS_LITERAL_STRING("hdr"));
+    }
+}
+
+bool
+WebGLExtensionCompressedTextureASTC::IsSupported(const WebGLContext* webgl)
+{
+    gl::GLContext* gl = webgl->GL();
+    return gl->IsExtensionSupported(gl::GLContext::KHR_texture_compression_astc_ldr);
+}
+
+IMPL_WEBGL_EXTENSION_GOOP(WebGLExtensionCompressedTextureASTC, WEBGL_compressed_texture_astc)
+
+} // namespace mozilla

--- a/dom/canvas/WebGLExtensions.h
+++ b/dom/canvas/WebGLExtensions.h
@@ -2,25 +2,27 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #ifndef WEBGL_EXTENSIONS_H_
 #define WEBGL_EXTENSIONS_H_
 
 #include "mozilla/AlreadyAddRefed.h"
+#include "nsString.h"
+#include "nsTArray.h"
 #include "nsWrapperCache.h"
 #include "WebGLObjectModel.h"
 #include "WebGLTypes.h"
 
 namespace mozilla {
 
 namespace dom {
-template<typename T>
-class Sequence;
+template<typename> struct Nullable;
+template<typename> class Sequence;
 } // namespace dom
 
 namespace webgl {
 class FormatUsageAuthority;
 } // namespace webgl
 
 class WebGLContext;
 class WebGLShader;
@@ -55,16 +57,32 @@ protected:
     virtual JSObject* WrapObject(JSContext* cx, JS::Handle<JSObject*> givenProto) override;
 
 #define IMPL_WEBGL_EXTENSION_GOOP(WebGLExtensionType, WebGLBindingType)\
     JSObject*                                                    \
     WebGLExtensionType::WrapObject(JSContext* cx, JS::Handle<JSObject*> givenProto) {              \
         return dom::WebGLBindingType##Binding::Wrap(cx, this, givenProto); \
     }
 
+////
+
+class WebGLExtensionCompressedTextureASTC
+    : public WebGLExtensionBase
+{
+public:
+    explicit WebGLExtensionCompressedTextureASTC(WebGLContext* webgl);
+    virtual ~WebGLExtensionCompressedTextureASTC();
+
+    void GetSupportedProfiles(dom::Nullable< nsTArray<nsString> >& retval) const;
+
+    static bool IsSupported(const WebGLContext* webgl);
+
+    DECL_WEBGL_EXTENSION_GOOP
+};
+
 class WebGLExtensionCompressedTextureATC
     : public WebGLExtensionBase
 {
 public:
     explicit WebGLExtensionCompressedTextureATC(WebGLContext*);
     virtual ~WebGLExtensionCompressedTextureATC();
 
     DECL_WEBGL_EXTENSION_GOOP

--- a/dom/canvas/WebGLFormats.cpp
+++ b/dom/canvas/WebGLFormats.cpp
@@ -108,16 +108,47 @@ InitCompressedFormatInfo()
     AddCompressedFormatInfo(EffectiveFormat::ATC_RGBA_INTERPOLATED_ALPHA_AMD, 128, 4, 4, CompressionFamily::ATC);
 
     // EXT_texture_compression_s3tc
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGB_S3TC_DXT1_EXT ,  64, 4, 4, CompressionFamily::S3TC);
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_S3TC_DXT1_EXT,  64, 4, 4, CompressionFamily::S3TC);
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_S3TC_DXT3_EXT, 128, 4, 4, CompressionFamily::S3TC);
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_S3TC_DXT5_EXT, 128, 4, 4, CompressionFamily::S3TC);
 
+    // KHR_texture_compression_astc_ldr
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_4x4_KHR          , 128,  4,  4, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_5x4_KHR          , 128,  5,  4, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_5x5_KHR          , 128,  5,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_6x5_KHR          , 128,  6,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_6x6_KHR          , 128,  6,  6, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_8x5_KHR          , 128,  8,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_8x6_KHR          , 128,  8,  6, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_8x8_KHR          , 128,  8,  8, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_10x5_KHR         , 128, 10,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_10x6_KHR         , 128, 10,  6, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_10x8_KHR         , 128, 10,  8, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_10x10_KHR        , 128, 10, 10, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_12x10_KHR        , 128, 12, 10, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_ASTC_12x12_KHR        , 128, 12, 12, CompressionFamily::ASTC);
+
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR  , 128,  4,  4, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR  , 128,  5,  4, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR  , 128,  5,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR  , 128,  6,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR  , 128,  6,  6, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR  , 128,  8,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR  , 128,  8,  6, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR  , 128,  8,  8, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR , 128, 10,  5, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR , 128, 10,  6, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR , 128, 10,  8, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR, 128, 10, 10, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR, 128, 12, 10, CompressionFamily::ASTC);
+    AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR, 128, 12, 12, CompressionFamily::ASTC);
+
     // IMG_texture_compression_pvrtc
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGB_PVRTC_4BPPV1 , 256,  8, 8, CompressionFamily::PVRTC);
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_PVRTC_4BPPV1, 256,  8, 8, CompressionFamily::PVRTC);
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGB_PVRTC_2BPPV1 , 256, 16, 8, CompressionFamily::PVRTC);
     AddCompressedFormatInfo(EffectiveFormat::COMPRESSED_RGBA_PVRTC_2BPPV1, 256, 16, 8, CompressionFamily::PVRTC);
 
     // OES_compressed_ETC1_RGB8_texture
     AddCompressedFormatInfo(EffectiveFormat::ETC1_RGB8_OES, 64, 4, 4, CompressionFamily::ETC1);
@@ -287,16 +318,47 @@ InitFormatInfo()
     AddFormatInfo(FOO(ATC_RGBA_INTERPOLATED_ALPHA_AMD), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
 
     // EXT_texture_compression_s3tc
     AddFormatInfo(FOO(COMPRESSED_RGB_S3TC_DXT1_EXT ), 0, 1,1,1,0, 0,0, UnsizedFormat::RGB , false, ComponentType::NormUInt);
     AddFormatInfo(FOO(COMPRESSED_RGBA_S3TC_DXT1_EXT), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
     AddFormatInfo(FOO(COMPRESSED_RGBA_S3TC_DXT3_EXT), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
     AddFormatInfo(FOO(COMPRESSED_RGBA_S3TC_DXT5_EXT), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
 
+    // KHR_texture_compression_astc_ldr
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_4x4_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_5x4_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_5x5_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_6x5_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_6x6_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_8x5_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_8x6_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_8x8_KHR          ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_10x5_KHR         ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_10x6_KHR         ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_10x8_KHR         ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_10x10_KHR        ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_12x10_KHR        ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_RGBA_ASTC_12x12_KHR        ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
+
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR  ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR ), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+    AddFormatInfo(FOO(COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, true , ComponentType::NormUInt);
+
     // IMG_texture_compression_pvrtc
     AddFormatInfo(FOO(COMPRESSED_RGB_PVRTC_4BPPV1 ), 0, 1,1,1,0, 0,0, UnsizedFormat::RGB , false, ComponentType::NormUInt);
     AddFormatInfo(FOO(COMPRESSED_RGBA_PVRTC_4BPPV1), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
     AddFormatInfo(FOO(COMPRESSED_RGB_PVRTC_2BPPV1 ), 0, 1,1,1,0, 0,0, UnsizedFormat::RGB , false, ComponentType::NormUInt);
     AddFormatInfo(FOO(COMPRESSED_RGBA_PVRTC_2BPPV1), 0, 1,1,1,1, 0,0, UnsizedFormat::RGBA, false, ComponentType::NormUInt);
 
     // OES_compressed_ETC1_RGB8_texture
     AddFormatInfo(FOO(ETC1_RGB8_OES), 0, 1,1,1,0, 0,0, UnsizedFormat::RGB, false, ComponentType::NormUInt);

--- a/dom/canvas/WebGLFormats.h
+++ b/dom/canvas/WebGLFormats.h
@@ -114,16 +114,47 @@ enum class EffectiveFormat : EffectiveFo
     ATC_RGBA_INTERPOLATED_ALPHA_AMD,
 
     // EXT_texture_compression_s3tc
     COMPRESSED_RGB_S3TC_DXT1_EXT,
     COMPRESSED_RGBA_S3TC_DXT1_EXT,
     COMPRESSED_RGBA_S3TC_DXT3_EXT,
     COMPRESSED_RGBA_S3TC_DXT5_EXT,
 
+    // KHR_texture_compression_astc_ldr
+    COMPRESSED_RGBA_ASTC_4x4_KHR,
+    COMPRESSED_RGBA_ASTC_5x4_KHR,
+    COMPRESSED_RGBA_ASTC_5x5_KHR,
+    COMPRESSED_RGBA_ASTC_6x5_KHR,
+    COMPRESSED_RGBA_ASTC_6x6_KHR,
+    COMPRESSED_RGBA_ASTC_8x5_KHR,
+    COMPRESSED_RGBA_ASTC_8x6_KHR,
+    COMPRESSED_RGBA_ASTC_8x8_KHR,
+    COMPRESSED_RGBA_ASTC_10x5_KHR,
+    COMPRESSED_RGBA_ASTC_10x6_KHR,
+    COMPRESSED_RGBA_ASTC_10x8_KHR,
+    COMPRESSED_RGBA_ASTC_10x10_KHR,
+    COMPRESSED_RGBA_ASTC_12x10_KHR,
+    COMPRESSED_RGBA_ASTC_12x12_KHR,
+
+    COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR,
+    COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR,
+
     // IMG_texture_compression_pvrtc
     COMPRESSED_RGB_PVRTC_4BPPV1,
     COMPRESSED_RGBA_PVRTC_4BPPV1,
     COMPRESSED_RGB_PVRTC_2BPPV1,
     COMPRESSED_RGBA_PVRTC_2BPPV1,
 
     // OES_compressed_ETC1_RGB8_texture
     ETC1_RGB8_OES,
@@ -168,21 +199,22 @@ enum class ComponentType : uint8_t {
     UInt,         // RGBA32UI, STENCIL_INDEX8
     NormInt,      // RGBA8_SNORM
     NormUInt,     // RGBA8, DEPTH_COMPONENT16
     Float,        // RGBA32F
     Special,      // DEPTH24_STENCIL8
 };
 
 enum class CompressionFamily : uint8_t {
-    ETC1,
-    ES3, // ETC2 or EAC
+    ASTC,
     ATC,
+    ES3, // ETC2 or EAC
+    ETC1,
+    PVRTC,
     S3TC,
-    PVRTC,
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 
 struct CompressedFormatInfo
 {
     const EffectiveFormat effectiveFormat;
     const uint8_t bytesPerBlock;

--- a/dom/canvas/WebGLTextureUpload.cpp
+++ b/dom/canvas/WebGLTextureUpload.cpp
@@ -934,16 +934,26 @@ ValidateCompressedTexImageRestrictions(c
 
         if (level == 0)
             return false;
 
         return (size == 0 || size == 1 || size == 2);
     };
 
     switch (format->compression->family) {
+    case webgl::CompressionFamily::ASTC:
+        if (target == LOCAL_GL_TEXTURE_3D &&
+            !webgl->gl->IsExtensionSupported(gl::GLContext::KHR_texture_compression_astc_hdr))
+        {
+            webgl->ErrorInvalidOperation("%s: TEXTURE_3D requires ASTC's hdr profile.",
+                                         funcName);
+            return false;
+        }
+        break;
+
     case webgl::CompressionFamily::PVRTC:
         if (!IsPowerOfTwo(width) || !IsPowerOfTwo(height)) {
             webgl->ErrorInvalidValue("%s: %s requires power-of-two width and height.",
                                      funcName, format->name);
             return false;
         }
 
         break;

--- a/dom/canvas/WebGLTypes.h
+++ b/dom/canvas/WebGLTypes.h
@@ -152,16 +152,17 @@ enum class WebGLExtensionID : uint8_t {
     OES_element_index_uint,
     OES_standard_derivatives,
     OES_texture_float,
     OES_texture_float_linear,
     OES_texture_half_float,
     OES_texture_half_float_linear,
     OES_vertex_array_object,
     WEBGL_color_buffer_float,
+    WEBGL_compressed_texture_astc,
     WEBGL_compressed_texture_atc,
     WEBGL_compressed_texture_etc,
     WEBGL_compressed_texture_etc1,
     WEBGL_compressed_texture_pvrtc,
     WEBGL_compressed_texture_s3tc,
     WEBGL_debug_renderer_info,
     WEBGL_debug_shaders,
     WEBGL_depth_texture,

--- a/dom/canvas/moz.build
+++ b/dom/canvas/moz.build
@@ -103,16 +103,17 @@ UNIFIED_SOURCES += [
     'WebGLContextValidate.cpp',
     'WebGLContextVertexArray.cpp',
     'WebGLContextVertices.cpp',
     'WebGLElementArrayCache.cpp',
     'WebGLExtensionBase.cpp',
     'WebGLExtensionBlendMinMax.cpp',
     'WebGLExtensionColorBufferFloat.cpp',
     'WebGLExtensionColorBufferHalfFloat.cpp',
+    'WebGLExtensionCompressedTextureASTC.cpp',
     'WebGLExtensionCompressedTextureATC.cpp',
     'WebGLExtensionCompressedTextureES3.cpp',
     'WebGLExtensionCompressedTextureETC1.cpp',
     'WebGLExtensionCompressedTexturePVRTC.cpp',
     'WebGLExtensionCompressedTextureS3TC.cpp',
     'WebGLExtensionDebugRendererInfo.cpp',
     'WebGLExtensionDebugShaders.cpp',
     'WebGLExtensionDepthTexture.cpp',

--- a/gfx/gl/GLContext.cpp
+++ b/gfx/gl/GLContext.cpp
@@ -152,16 +152,18 @@ static const char* const sExtensionNames
     "GL_EXT_texture_storage",
     "GL_EXT_timer_query",
     "GL_EXT_transform_feedback",
     "GL_EXT_unpack_subimage",
     "GL_IMG_read_format",
     "GL_IMG_texture_compression_pvrtc",
     "GL_IMG_texture_npot",
     "GL_KHR_debug",
+    "GL_KHR_texture_compression_astc_hdr",
+    "GL_KHR_texture_compression_astc_ldr",
     "GL_NV_draw_instanced",
     "GL_NV_fence",
     "GL_NV_framebuffer_blit",
     "GL_NV_geometry_program4",
     "GL_NV_half_float",
     "GL_NV_instanced_arrays",
     "GL_NV_primitive_restart",
     "GL_NV_texture_barrier",

--- a/gfx/gl/GLContext.h
+++ b/gfx/gl/GLContext.h
@@ -475,16 +475,18 @@ public:
         EXT_texture_storage,
         EXT_timer_query,
         EXT_transform_feedback,
         EXT_unpack_subimage,
         IMG_read_format,
         IMG_texture_compression_pvrtc,
         IMG_texture_npot,
         KHR_debug,
+        KHR_texture_compression_astc_hdr,
+        KHR_texture_compression_astc_ldr,
         NV_draw_instanced,
         NV_fence,
         NV_framebuffer_blit,
         NV_geometry_program4,
         NV_half_float,
         NV_instanced_arrays,
         NV_primitive_restart,
         NV_texture_barrier,