bugfix: NullPointerException prevented to optional extras (if there is no extra at all)
bugfix: NullPointerException prevented to optional extras (if there is no extra at all)

AbnerLv/dart,jug6ernaut/saber,MaTriXy/saber,f2prateek/dart,MaTriXy/dart,bryant1410/dart,bryant1410/dart,pakoito/dart,brunodles/dart,brunodles/dart,jug6ernaut/saber,pakoito/dart,stephanenicolas/dart,AbnerLv/dart,MaTriXy/dart,f2prateek/dart,stephanenicolas/dart,MaTriXy/saber