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Author: Lms24

packages/browser-utils/src/metrics/browserMetrics.ts

@@ -541,6 +541,9 @@ export function _addResourceSpans(
   setResourceEntrySizeData(attributes, entry, 'decodedBodySize', 'http.decoded_response_content_length');
 
   if (entry.deliveryType != null) {
+    // Falling back to 'default' as attributes with empty string are dropped by our backend.
+    // The empty string is the default value for the deliveryType attribute, indicating that
+    // the browser actually sent a request (as opposed to retrieved the response from its cache).
     attributes['http.response_delivery_type'] = entry.deliveryType || 'default';
   }