ok, my description was not good. i don't mean front view i mean greasepencils settings/viewport display settings depth ordering has to be set to front while in stroke placement: stroke mode.

Hello Antonio Vazquez again,
you are bugfixing at the speed of light!
Now also the surface projection works! In one situation some vertices of the strokes snapped to the lower left corner, maybe the world origin, but i was not able to reproduce it for a second time yet.

Now it sits paralell to the camera plane but drawing on the surface from camera view won't work.