Android KitKat: Snackbar is not in the bottom of the screen

If you use 26 or 27 support, it is probably this known bug: Google Issue Tracker: Snackbar wrong placement on the Android 4x versions

To workaround it, use a small time delay before showing the Snackbar. This is needed if you want to show the Snackbar immediately when the screen displays, in onCreateView() or onCreate().

new Handler().postDelayed(new Runnable() {
    @Override
    public void run() {
        // For com.android.support:design:v26 or v27, use a small
        // time delay, to prevent bottom gap bug on Android 4.4
        if (isAdded()) { snackbar.show(); }
    }
}, 500);

Because you have a time delay, remember to protect against null Activity by checking for isAdded() or check getActivity() != null.