Application level logging in a trigger

Questions
3

Yes, they do!

12:37:16.598 [TriggerService-akka.actor.default-dispatcher-14] DEBUG daml.tracelog - [unknown source]: "Debug message from TriggerA"

adding

    <logger name="daml.tracelog" level="DEBUG">
        <appender-ref ref="STDOUT"/>
    </logger>

to the trigger-service-logback.xml file, and reverting the default level to INFO, does the trick.