"opentracing" logger depends on default's logger level

[TertiumOrganum1]

To store trace-logs to different location (or stream) I declare "opentracing" logger, which is used by userver under the hood. But its level field ignored (you may even skip it) because output of traces depends on default logger's level, i.e. you can't set log level to warning, tracing to info separately.

        tracer:
            service-name: $service-name
        logging:
            fs-task-processor: fs-task-processor
            loggers:
                default:
                    file_path: '@stderr'
                    level: info
                    overflow_behavior: discard  # Drop logs if the system is too busy to write them down.
                opentracing:
                    format: ltsv
                    file_path: '@stdout'                    
                    overflow_behavior: discard 

Expected behavior of different loggers - independent level parameter.