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+
+System Add-on Diagnostics Ping
+==============================
+
+This ping is generated by an add-on created by Mozilla and shipped to users on current Firefox beta and release (51,52).
+The ping contains information about successful install and startup of the diagnostic add-on, to diagnose suspected delivery and installation problems.
+
+Structure:
+
+.. code-block:: js
+
+    {
+      type: "system-addon-deployment-diagnostics",
+      ...
+      clientId: <UUID>,
+      environment: { ... },
+      // Common ping data.
+      payload: {
+        // The version of the diagnostic add-on - future versions are planned.
+        version: <int>,
+        // The installation phase that has completed successfully - either "install" or "startup"
+        phase: <string>,
+      }
+    }