{"json_modified": "2016-09-18T19:36:27.669601", "uuid": "eed32cba-66fd-4a66-b0d7-4da0349c578d", "title": "webRequest.onBeforeRequest", "url": "/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webRequest/onBeforeRequest", "tags": ["API", "webRequest", "Reference", "Event", "Non-standard", "Extensions", "Add-ons", "WebExtensions", "onBeforeRequest", "Non-Standard", "add-ons"], "translations": [], "modified": "2016-09-18T19:36:27", "label": "webRequest.onBeforeRequest", "localization_tags": [], "locale": "en-US", "id": 166921, "last_edit": "2016-09-18T18:56:23", "summary": "This event is triggered when a request is about to be made, and before headers are available. This is a good place to listen if you want to cancel or redirect the request.", "sections": [{"id": "Quick_Links", "title": null}, {"id": "Syntax", "title": "Syntax"}, {"id": "addListener_syntax", "title": "addListener syntax"}, {"id": "Parameters", "title": "Parameters"}, {"id": "Additional_objects", "title": "Additional objects"}, {"id": "details", "title": "details"}, {"id": "Browser_compatibility", "title": "Browser compatibility"}, {"id": "Compatibility_notes", "title": "Compatibility notes"}, {"id": "Chrome", "title": "Chrome"}, {"id": "Firefox", "title": "Firefox"}, {"id": "Firefox_for_Android", "title": "Firefox for Android"}, {"id": "Opera", "title": "Opera"}, {"id": "Examples", "title": "Examples"}], "slug": "Mozilla/Add-ons/WebExtensions/API/webRequest/onBeforeRequest", "review_tags": []}