the last problem was, that the developer tool was crashed and did not reload the changes.
no error message etc.
Restarted and it was working immediatelly.
So I will keep this in mind and reboot the Developer tool more often 
the last problem was, that the developer tool was crashed and did not reload the changes.
no error message etc.
Restarted and it was working immediatelly.
So I will keep this in mind and reboot the Developer tool more often