diff --git a/gfx/gl/GLContext.cpp b/gfx/gl/GLContext.cpp
index 29fbc2da9b3..6e1e80af57e 100644
--- a/gfx/gl/GLContext.cpp
+++ b/gfx/gl/GLContext.cpp
@@ -494,7 +494,6 @@ GLContext::InitWithPrefix(const char *prefix, bool trygl)
 
         if (IsExtensionSupported(XXX_framebuffer_multisample))
         {
-            MOZ_ASSERT(SupportsSplitFramebuffer());
             SymLoadStruct auxSymbols[] = {
                 {
                     (PRFuncPtr*) &mSymbols.fRenderbufferStorageMultisample,
@@ -698,7 +697,7 @@ GLContext::InitWithPrefix(const char *prefix, bool trygl)
         mMaxTextureImageSize = mMaxTextureSize;
 
         mMaxSamples = 0;
-        if (SupportsFramebufferMultisample()) {
+        if (IsExtensionSupported(XXX_framebuffer_multisample)) {
             fGetIntegerv(LOCAL_GL_MAX_SAMPLES, (GLint*)&mMaxSamples);
         }
 
diff --git a/gfx/gl/GLContext.h b/gfx/gl/GLContext.h
index ca5f5baf5c9..c803c14720b 100644
--- a/gfx/gl/GLContext.h
+++ b/gfx/gl/GLContext.h
@@ -502,23 +502,6 @@ private:
     bool MarkExtensionGroupUnsupported(GLExtensionGroup extensionGroup);
 
 
-// -----------------------------------------------------------------------------
-// Deprecated extension group queries (use XXX_* instead)
-public:
-
-    bool SupportsFramebufferMultisample() const {
-        return IsExtensionSupported(XXX_framebuffer_multisample);
-    }
-
-    bool HasExt_FramebufferBlit() const {
-        return IsExtensionSupported(XXX_framebuffer_blit);
-    }
-
-    bool SupportsSplitFramebuffer() const {
-        return IsExtensionSupported(XXX_framebuffer_blit);
-    }
-
-
 // -----------------------------------------------------------------------------
 // Robustness handling
 public:
@@ -2568,8 +2551,9 @@ public:
         if (mScreen)
             return mScreen->GetReadFB();
 
-        GLenum bindEnum = SupportsSplitFramebuffer() ? LOCAL_GL_READ_FRAMEBUFFER_BINDING_EXT
-                                                     : LOCAL_GL_FRAMEBUFFER_BINDING;
+        GLenum bindEnum = IsExtensionSupported(XXX_framebuffer_blit)
+                            ? LOCAL_GL_READ_FRAMEBUFFER_BINDING_EXT
+                            : LOCAL_GL_FRAMEBUFFER_BINDING;
 
         GLuint ret = 0;
         GetUIntegerv(bindEnum, &ret);
diff --git a/gfx/gl/GLScreenBuffer.cpp b/gfx/gl/GLScreenBuffer.cpp
index 21becd7212e..5dd2fbf9725 100644
--- a/gfx/gl/GLScreenBuffer.cpp
+++ b/gfx/gl/GLScreenBuffer.cpp
@@ -29,7 +29,7 @@ GLScreenBuffer::Create(GLContext* gl,
                      const SurfaceCaps& caps)
 {
     if (caps.antialias &&
-        !gl->SupportsFramebufferMultisample())
+        !gl->IsExtensionSupported(GLContext::XXX_framebuffer_multisample))
     {
         return nullptr;
     }
@@ -79,7 +79,7 @@ GLScreenBuffer::BindAsFramebuffer(GLContext* const gl, GLenum target) const
     GLuint drawFB = DrawFB();
     GLuint readFB = ReadFB();
 
-    if (!gl->HasExt_FramebufferBlit()) {
+    if (!gl->IsExtensionSupported(GLContext::XXX_framebuffer_blit)) {
         MOZ_ASSERT(drawFB == readFB);
         gl->raw_fBindFramebuffer(target, readFB);
         return;
@@ -92,14 +92,14 @@ GLScreenBuffer::BindAsFramebuffer(GLContext* const gl, GLenum target) const
         break;
 
     case LOCAL_GL_DRAW_FRAMEBUFFER_EXT:
-        if (!gl->HasExt_FramebufferBlit())
+        if (!gl->IsExtensionSupported(GLContext::XXX_framebuffer_blit))
             NS_WARNING("DRAW_FRAMEBUFFER requested but unavailable.");
 
         gl->raw_fBindFramebuffer(LOCAL_GL_DRAW_FRAMEBUFFER_EXT, drawFB);
         break;
 
     case LOCAL_GL_READ_FRAMEBUFFER_EXT:
-        if (!gl->HasExt_FramebufferBlit())
+        if (!gl->IsExtensionSupported(GLContext::XXX_framebuffer_blit))
             NS_WARNING("READ_FRAMEBUFFER requested but unavailable.");
 
         gl->raw_fBindFramebuffer(LOCAL_GL_READ_FRAMEBUFFER_EXT, readFB);
@@ -124,7 +124,7 @@ GLScreenBuffer::BindFB(GLuint fb)
     if (mInternalDrawFB == mInternalReadFB) {
         mGL->raw_fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, mInternalDrawFB);
     } else {
-        MOZ_ASSERT(mGL->SupportsSplitFramebuffer());
+        MOZ_ASSERT(mGL->IsExtensionSupported(GLContext::XXX_framebuffer_blit));
         mGL->raw_fBindFramebuffer(LOCAL_GL_DRAW_FRAMEBUFFER_EXT, mInternalDrawFB);
         mGL->raw_fBindFramebuffer(LOCAL_GL_READ_FRAMEBUFFER_EXT, mInternalReadFB);
     }
@@ -138,7 +138,7 @@ GLScreenBuffer::BindFB(GLuint fb)
 void
 GLScreenBuffer::BindDrawFB(GLuint fb)
 {
-    if (!mGL->SupportsSplitFramebuffer()) {
+    if (!mGL->IsExtensionSupported(GLContext::XXX_framebuffer_blit)) {
         NS_WARNING("DRAW_FRAMEBUFFER requested, but unsupported.");
 
         mGL->raw_fBindFramebuffer(LOCAL_GL_DRAW_FRAMEBUFFER_EXT, fb);
@@ -158,7 +158,7 @@ GLScreenBuffer::BindDrawFB(GLuint fb)
 void
 GLScreenBuffer::BindReadFB(GLuint fb)
 {
-    if (!mGL->SupportsSplitFramebuffer()) {
+    if (!mGL->IsExtensionSupported(GLContext::XXX_framebuffer_blit)) {
         NS_WARNING("READ_FRAMEBUFFER requested, but unsupported.");
 
         mGL->raw_fBindFramebuffer(LOCAL_GL_READ_FRAMEBUFFER_EXT, fb);
@@ -233,7 +233,7 @@ GLScreenBuffer::GetReadFB() const
     // We use raw_ here because this is debug code and we need to see what
     // the driver thinks.
     GLuint actual = 0;
-    if (mGL->SupportsSplitFramebuffer())
+    if (mGL->IsExtensionSupported(GLContext::XXX_framebuffer_blit))
         mGL->raw_fGetIntegerv(LOCAL_GL_READ_FRAMEBUFFER_BINDING_EXT, (GLint*)&actual);
     else
         mGL->raw_fGetIntegerv(LOCAL_GL_FRAMEBUFFER_BINDING, (GLint*)&actual);