//renderer process
const flags = ['disabled'];
    currentWindow.setThumbarButtons([{
        tooltip: 'rewind',
        icon: path.join(__dirname, 'rewind.png'),
        flags
    }, {
        tooltip: this.state === 'play' ? 'pause' : 'play',
        icon: path.join(__dirname, 'play.png'),
        flags
    }, {
        tooltip: 'forward',
        icon: path.join(__dirname, 'forward.png'),
        flags
    }]);