Defines where expand icon is displayed. The toggleAlign property specifies where expand icon is displayed. It can be display either on left or right of the node. You can define it during object creation: let sidebar = new w2sidebar({ name : 'sidebar', toggleAlign: 'left', nodes: [ { id: 'id-1', text: 'Level 1' }, { id: 'id-2', text: 'Level 2' }, { id: 'id-3', text: 'Level 3' } ] }); Or any time after the object has been created: w2ui.sidebar.toggleAlign = 'left'; w2ui.sidebar.refresh();