I start from scratch with an empty ODB, then start the logger and the example frontend. When attempting to start a run, the logger complains
[Logger,ERROR] [mlogger.cxx:3739:log_create_writer,ERROR] channel requested GZIP/ZLIB compression, output module must be FILE
And apparently does not write any data. Even more confusing is that the run starts successfully, so it takes some time to realize the problem.
Another (minor) confusing issue we have is that "Output" must be set to "File" and "Type" (which is the second entry in the logging channel settings) must be set to "Disk". I guess the "Type" is now ignored, is that correct? In that case it should be removed.