Sollte man vielleicht noch erwähnen, wo man das tolle Teil findet - und zwar hier:
Can I get rid of those annoying messages in the green bar of flightsim?
Yes! To get rid of all messages (so also joined/leaved):
* Go to http://www.schiratti.com/dowson.html
* Download AdvDisp 2.14 and place the DLL file in your FlightSim modules directory
* In FS, click on Modules -> ADV Display
* In the winow that appears, right klick into the black area and select "Hide always"