--- a/xpcom/threads/nsThread.cpp
+++ b/xpcom/threads/nsThread.cpp
@@ -1436,16 +1436,19 @@ nsThread::ProcessNextEvent(bool aMayWait
 
         // Copy the name into sMainThreadRunnableName's buffer, and append a
         // terminating null.
         uint32_t length = std::min((uint32_t) kRunnableNameBufSize - 1,
                                    (uint32_t) name.Length());
         memcpy(sMainThreadRunnableName.begin(), name.BeginReading(), length);
         sMainThreadRunnableName[length] = '\0';
       }
+
+      AUTO_PROFILER_LABEL_DYNAMIC("nsThread::ProcessNextEvent", EVENTS,
+                                  name.get());
 #endif
 
       event->Run();
     } else if (aMayWait) {
       MOZ_ASSERT(ShuttingDown(),
                  "This should only happen when shutting down");
       rv = NS_ERROR_UNEXPECTED;
     }