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Author: zhumin8

oauth2_http/java/com/google/auth/oauth2/Slf4jUtils.java

@@ -142,6 +142,8 @@ static void logWithMDC(
         // Default to DEBUG level
     }
     if (!contextMap.isEmpty()) {
+      // MDC carries contextual information in log messages.
+      // It is tied to thread, and is safer to clear it as we intend to tie info to log entries.
       MDC.clear();
     }
   }