{"json_modified": "2016-03-28T08:24:05.843539", "uuid": "b68a3207-2372-4709-869a-c7586b5eeeca", "title": "popupshowing", "url": "/en-US/docs/Web/Events/popupshowing", "tags": [], "translations": [], "modified": "2014-06-19T01:32:09", "label": "popupshowing", "localization_tags": [], "locale": "en-US", "id": 56575, "last_edit": "2014-06-19T01:32:09", "summary": "The <code>popupshowing</code> event is executed when a <a href=\"/en-US/docs/XUL/menupopup\"><code>&lt;menupopup&gt;</code></a>, <a href=\"/en-US/docs/XUL/panel\"><code>&lt;panel&gt;</code></a> or <a href=\"/en-US/docs/XUL/tooltip\"><code>&lt;tooltip&gt;</code></a> is about to become visible. The default action of the event can be <a href=\"/en-US/docs/DOM/event.preventDefault\" title=\"/en-US/docs/DOM/event.preventDefault\">prevented</a> to prevent the popup to appear.", "sections": [{"id": "General_info", "title": "General info"}, {"id": "Properties", "title": "Properties"}], "slug": "Web/Events/popupshowing", "review_tags": []}