Eclipse Mars 2 Console doesn't show building process

Question

since some days ago the console output window doesn't show nor the building process neither the the building errors any more.

The window remains white, even if I build all the projects - as well as the progress-window.

The console still shows the running output of the projects and if the code is ok, the projects are working. So I think the compilation is working, but not shown.

Any ideas?

Thanks