Why do single apps override launcher setting to not show statusbar and how to avoid this? Using GO LAUNCHER EX I disabled statusbar, but when starting Firefox the statusbar shows up again, dolpin hd doesn't csuse this behavior. Is there any hack or app to generally not show the statusbar?
Sorry, but you cant prevent this. 
The developer can set in the AndroidManifest.xml if the Activity (the screen you see) hide the statusbar or not. This is the setting, if you are interested in: @android:style/Theme.NoTitleBar