Flutter - Navigator.pop(context) calls methods of the screen we are leaving

Question

When leaving a page via Navigator.pop(context) the method defined in MaterialApps routes:

"/routeName": (context) {
        doSomething();
        doSomethingElse();
        return MyScreen(request: data,);
      },

is called (as when entering the page).

This only happens on two specific sites and I do not have an idea why.

Does anyone have an idea what could cause this behaviour?