Gantt APITemplatesgrid_folderOn this pagegrid_folder Description Specifies the icon of parent items in the tree column grid_folder: (task: Task) => string;Parameters task - (required) Task - the task object Returns text - (string) - html text which will be rendered in the gantt Examplegantt.templates.grid_folder = function(item) { return `<div className='gantt_tree_icon gantt_folder_${(item.$open ? "open" : "closed")}'> </div>`;};Related Guides Templates of the Grid Configuring the Tree Column