String getStringProperty(String name) {
        String prop = null;
        try {
            prop = System.getProperty(name);
        } catch (SecurityException e) {
            ; // Ignore
        }
        return (prop == null) ? properties.getProperty(name) : prop;
    }
See https://jira.qos.ch/browse/SLF4J-499
@since 1.7.33 and 2.0.0-alpha6
slf4j-simple/src/main/java/org/slf4j/simple/SimpleLoggerConfiguration.java