Before (Log4j 1.x)
log4j.appender.Console.layout=org.alfresco.util.log.log4j.SanitizingPatternLayout
log4j.appender.Console.layout.ConversionPattern=%d{ISO8601} %x %-5p [%c{3}] [%t] %m%n
After (Log4j 2.x)
appender.console.layout.type=PatternLayout
appender.console.layout.pattern=%d{ISO8601} %x %-5p [%c{3}] [%t] %replace{%m}{[\r\n]+}{}%n
Notice the usage of the %replace{%m}{[\r\n]+}{} layout parameter to make sure logs are properly sanitized.