How to reproduce:
Open email, try to answer with a response ("Schnellantwort")
Actual results:
When first opening an email, the button "responses" is not shown/visible (see screenshot 1) --> one first has to click on "reply" in order to get a new view with new and different new options offered - among them also "responses" (see screenshot 2).
The user thus has to "take the crucial step in his head", namely that "responses" (Schnellantwort) are a suboption of "reply" ("Antworten").
Expected results:
Maybe one could add the button "responses" between to "reply", "reply all" and "forward" in order to make it be found more easily.