Can't start optimus manager via GUI

Hi there, I have a laptop with an Intel chipset and a dedicated NVidia graphics card (GeForce MX250). So far I’ve been using optimus-manager and optimus-manager-qt under Manjaro Gnome following these instructions

without any problem. Lately the tray symbol doesn’t show anymore and I can’t start optimus-manager via GUI either. Could it be related to the new NVidia drivers?