--- a/gfx/gl/GLLibraryEGL.cpp
+++ b/gfx/gl/GLLibraryEGL.cpp
@@ -149,19 +149,22 @@ IsAccelAngleSupported(const nsCOMPtr<nsI
                       nsACString* const out_failureId)
 {
     int32_t angleSupport;
     nsCString failureId;
     gfxUtils::ThreadSafeGetFeatureStatus(gfxInfo,
                                          nsIGfxInfo::FEATURE_WEBGL_ANGLE,
                                          failureId,
                                          &angleSupport);
-    Telemetry::Accumulate(Telemetry::CANVAS_WEBGL_ACCL_FAILURE_ID,
-                          failureId);
-    if (failureId.IsEmpty()) {
+    if (failureId.IsEmpty() && angleSupport != nsIGfxInfo::FEATURE_STATUS_OK) {
+        // This shouldn't happen, if we see this it's because we've missed
+        // some failure paths
+        failureId = NS_LITERAL_CSTRING("FEATURE_FAILURE_ACCL_ANGLE_NOT_OK");
+    }
+    if (out_failureId->IsEmpty()) {
         *out_failureId = failureId;
     }
     return (angleSupport == nsIGfxInfo::FEATURE_STATUS_OK);
 }
 
 static EGLDisplay
 GetAndInitDisplay(GLLibraryEGL& egl, void* displayType)
 {
@@ -253,16 +256,20 @@ GetAndInitDisplayForAccelANGLE(GLLibrary
     if (d3d11ANGLE.IsEnabled()) {
         ret = GetAndInitDisplay(egl, LOCAL_EGL_D3D11_ELSE_D3D9_DISPLAY_ANGLE);
     }
 
     if (!ret) {
         ret = GetAndInitDisplay(egl, EGL_DEFAULT_DISPLAY);
     }
 
+    if (!ret) {
+        *out_failureId = NS_LITERAL_CSTRING("FEATURE_FAILURE_ACCL_ANGLE_NO_DISP");
+    }
+
     return ret;
 }
 
 bool
 GLLibraryEGL::ReadbackEGLImage(EGLImage image, gfx::DataSourceSurface* out_surface)
 {
     StaticMutexAutoUnlock lock(sMutex);
     if (!mReadbackGL) {
@@ -453,31 +460,49 @@ GLLibraryEGL::EnsureInitialized(bool for
 
     // Check the ANGLE support the system has
     nsCOMPtr<nsIGfxInfo> gfxInfo = do_GetService("@mozilla.org/gfx/info;1");
     mIsANGLE = IsExtensionSupported(ANGLE_platform_angle);
 
     EGLDisplay chosenDisplay = nullptr;
 
     if (IsExtensionSupported(ANGLE_platform_angle_d3d)) {
-        bool accelAngleSupport = IsAccelAngleSupported(gfxInfo, out_failureId);
+        nsCString accelAngleFailureId;
+        bool accelAngleSupport = IsAccelAngleSupported(gfxInfo, &accelAngleFailureId);
         bool shouldTryAccel = forceAccel || accelAngleSupport;
         bool shouldTryWARP = !forceAccel; // Only if ANGLE not supported or fails
 
         // If WARP preferred, will override ANGLE support
         if (gfxPrefs::WebGLANGLEForceWARP()) {
             shouldTryWARP = true;
             shouldTryAccel = false;
+            if (accelAngleFailureId.IsEmpty()) {
+                accelAngleFailureId = NS_LITERAL_CSTRING("FEATURE_FAILURE_FORCE_WARP");
+            }
         }
 
         // Hardware accelerated ANGLE path (supported or force accel)
         if (shouldTryAccel) {
             chosenDisplay = GetAndInitDisplayForAccelANGLE(*this, out_failureId);
         }
 
+        // Report the acceleration status to telemetry
+        if (!chosenDisplay) {
+            if (accelAngleFailureId.IsEmpty()) {
+                Telemetry::Accumulate(Telemetry::CANVAS_WEBGL_ACCL_FAILURE_ID,
+                                      NS_LITERAL_CSTRING("FEATURE_FAILURE_ACCL_ANGLE_UNKNOWN"));
+            } else {
+                Telemetry::Accumulate(Telemetry::CANVAS_WEBGL_ACCL_FAILURE_ID,
+                                      accelAngleFailureId);
+            }
+        } else {
+            Telemetry::Accumulate(Telemetry::CANVAS_WEBGL_ACCL_FAILURE_ID,
+                                  NS_LITERAL_CSTRING("SUCCESS"));
+        }
+
         // Fallback to a WARP display if ANGLE fails, or if WARP is forced
         if (!chosenDisplay && shouldTryWARP) {
             chosenDisplay = GetAndInitWARPDisplay(*this, EGL_DEFAULT_DISPLAY);
             if (!chosenDisplay) {
                 if (out_failureId->IsEmpty()) {
                     *out_failureId = NS_LITERAL_CSTRING("FEATURE_FAILURE_WARP_FALLBACK");
                 }
                 NS_ERROR("Fallback WARP context failed to initialize.");