{"action":"closed","issue":{"url":"https://api.github.com/repos/jpillora/xhook/issues/33","labels_url":"https://api.github.com/repos/jpillora/xhook/issues/33/labels{/name}","comments_url":"https://api.github.com/repos/jpillora/xhook/issues/33/comments","events_url":"https://api.github.com/repos/jpillora/xhook/issues/33/events","html_url":"https://github.com/jpillora/xhook/issues/33","id":53668524,"number":33,"title":"Calling .setRequestHeader before .open causes exception","user":{"login":"brendanyounger","id":970248,"avatar_url":"https://avatars.githubusercontent.com/u/970248?v=3","gravatar_id":"","url":"https://api.github.com/users/brendanyounger","html_url":"https://github.com/brendanyounger","followers_url":"https://api.github.com/users/brendanyounger/followers","following_url":"https://api.github.com/users/brendanyounger/following{/other_user}","gists_url":"https://api.github.com/users/brendanyounger/gists{/gist_id}","starred_url":"https://api.github.com/users/brendanyounger/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/brendanyounger/subscriptions","organizations_url":"https://api.github.com/users/brendanyounger/orgs","repos_url":"https://api.github.com/users/brendanyounger/repos","events_url":"https://api.github.com/users/brendanyounger/events{/privacy}","received_events_url":"https://api.github.com/users/brendanyounger/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/jpillora/xhook/labels/bug","name":"bug","color":"fc2929"}],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":1,"created_at":"2015-01-07T19:05:47Z","updated_at":"2015-04-28T09:12:28Z","closed_at":"2015-04-28T09:12:28Z","body":"Calling xhr.setRequestHeader('X-Blah', 'blah') before calling xhr.open() causes a type error since xhr.headerNames does not exist, so the code in setRequestHeader tries to dereference `undefined`."}}