Retopo: automatically snap newly created vertices?

When creating new edge loops during Retopology is there any way to automatically snap the newly created vertices to the surface? Right now I select each newly created vertex and make sure it is snapped properly.

I also have a shrinkwrap modifier.

How can I make my workflow more efficient in that regard?

Thank you very much in advance!

I use Draw Xray (with snapping option)

Hm, interesting. I will try that out. Thank you for the answer!