private static void emitTemporaryMDCAdapterWarningIfNeeded(SLF4JServiceProvider provider) {
        boolean isSubstitute = provider instanceof SubstituteServiceProvider;
        if(isSubstitute) {
            Reporter.info("Temporary mdcAdapter given by SubstituteServiceProvider.");
            Reporter.info("This mdcAdapter will be replaced after backend initialization has completed.");
        }
    }
An adapter to remove the key when done.
slf4j-api/src/main/java/org/slf4j/MDC.java