diff --git a/modules/ui/sidebar.js b/modules/ui/sidebar.js index da5028682..721baa37e 100644 --- a/modules/ui/sidebar.js +++ b/modules/ui/sidebar.js @@ -197,7 +197,7 @@ export function uiSidebar(context) { sidebar.toggleCollapse = function(shouldCollapse) { - if (d3_event) { + if (d3_event && typeof d3_event.preventDefault == 'function') { d3_event.preventDefault(); }