diff --git a/dom/canvas/WebGLContext.h b/dom/canvas/WebGLContext.h
index 78ea4dd47295..8dd1c36f410d 100644
--- a/dom/canvas/WebGLContext.h
+++ b/dom/canvas/WebGLContext.h
@@ -974,6 +974,7 @@ private:
     realGLboolean mScissorTestEnabled;
     realGLboolean mDepthTestEnabled;
     realGLboolean mStencilTestEnabled;
+    GLenum mGenerateMipmapHint;
 
     bool ValidateCapabilityEnum(GLenum cap, const char* info);
     realGLboolean* GetStateTrackingSlot(GLenum cap);
diff --git a/dom/canvas/WebGLContextGL.cpp b/dom/canvas/WebGLContextGL.cpp
index acf1e2222d38..a84aca590731 100644
--- a/dom/canvas/WebGLContextGL.cpp
+++ b/dom/canvas/WebGLContextGL.cpp
@@ -947,6 +947,8 @@ WebGLContext::Hint(GLenum target, GLenum mode)
 
     switch (target) {
     case LOCAL_GL_GENERATE_MIPMAP_HINT:
+        mGenerateMipmapHint = mode;
+
         // Deprecated and removed in desktop GL Core profiles.
         if (gl->IsCoreProfile())
             return;
diff --git a/dom/canvas/WebGLContextState.cpp b/dom/canvas/WebGLContextState.cpp
index 12f890df03cd..adb7fb7dd429 100644
--- a/dom/canvas/WebGLContextState.cpp
+++ b/dom/canvas/WebGLContextState.cpp
@@ -386,12 +386,15 @@ WebGLContext::GetParameter(JSContext* cx, GLenum pname, ErrorResult& rv)
         case LOCAL_GL_BLEND_DST_RGB:
         case LOCAL_GL_BLEND_DST_ALPHA:
         case LOCAL_GL_BLEND_EQUATION_RGB:
-        case LOCAL_GL_BLEND_EQUATION_ALPHA:
-        case LOCAL_GL_GENERATE_MIPMAP_HINT: {
+        case LOCAL_GL_BLEND_EQUATION_ALPHA: {
             GLint i = 0;
             gl->fGetIntegerv(pname, &i);
             return JS::NumberValue(uint32_t(i));
         }
+
+        case LOCAL_GL_GENERATE_MIPMAP_HINT:
+            return JS::NumberValue(mGenerateMipmapHint);
+
         case LOCAL_GL_IMPLEMENTATION_COLOR_READ_TYPE: {
             const webgl::FormatUsageInfo* usage;
             uint32_t width, height;
diff --git a/dom/canvas/WebGLContextValidate.cpp b/dom/canvas/WebGLContextValidate.cpp
index 03367140503a..1901ca10a05c 100644
--- a/dom/canvas/WebGLContextValidate.cpp
+++ b/dom/canvas/WebGLContextValidate.cpp
@@ -501,6 +501,7 @@ WebGLContext::InitAndValidateGL(FailureReason* const out_failReason)
     mDitherEnabled = true;
     mRasterizerDiscardEnabled = false;
     mScissorTestEnabled = false;
+    mGenerateMipmapHint = LOCAL_GL_DONT_CARE;
 
     // Bindings, etc.
     mActiveTexture = 0;