I'm reporting what I believe is a regression. After updating from v2.11.2 to v2.12.1, I noticed that the JSON log entries changed for my application:
Here is what I had in v2.11.2:
Here is what I got in v2.12.1:
I believe the offending commit is this. For some reason, the implementation of AbstractJacksonLayout#toSerializable(LogEvent, Writer) changed (the method call to convertMutableToLog4jEvent was deleted).