Configuration file specified by "logback.configurationFile" system property isn't applied when it doesn't have a .xml filename extension (file is perfectly valid text/xml, of course).

Log events generated by app are silently "fed" without a notice. No error or warning is reported regardless a "logback.debug" system property is set to "true". Full output on stdout by Logback is only the following (replace paths to your context):

17:23:19,659 |-INFO in ch.qos.logback.classic.LoggerContext[default] - Found resource [/home/libor/workspace/plexflow/misc/templates/logback.ui.xml2] at [
file:/home/libor/workspace/plexflow/misc/templates/logback.ui.xml2]

That's all. Actual log events events are logged nowhere in that case.