{"action":"created","issue":{"url":"https://api.github.com/repos/jquery/jquery/issues/2337","labels_url":"https://api.github.com/repos/jquery/jquery/issues/2337/labels{/name}","comments_url":"https://api.github.com/repos/jquery/jquery/issues/2337/comments","events_url":"https://api.github.com/repos/jquery/jquery/issues/2337/events","html_url":"https://github.com/jquery/jquery/issues/2337","id":78630133,"number":2337,"title":"Deprecate `which` property of the event object","user":{"login":"markelog","id":945528,"avatar_url":"https://avatars.githubusercontent.com/u/945528?v=3","gravatar_id":"","url":"https://api.github.com/users/markelog","html_url":"https://github.com/markelog","followers_url":"https://api.github.com/users/markelog/followers","following_url":"https://api.github.com/users/markelog/following{/other_user}","gists_url":"https://api.github.com/users/markelog/gists{/gist_id}","starred_url":"https://api.github.com/users/markelog/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/markelog/subscriptions","organizations_url":"https://api.github.com/users/markelog/orgs","repos_url":"https://api.github.com/users/markelog/repos","events_url":"https://api.github.com/users/markelog/events{/privacy}","received_events_url":"https://api.github.com/users/markelog/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/jquery/jquery/labels/Event","name":"Event","color":"0052cc"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":4,"created_at":"2015-05-20T18:09:30Z","updated_at":"2015-05-20T19:27:21Z","closed_at":null,"body":"In the https://api.jquery.com/category/events/event-object/, we have \r\n\r\n> The following properties are also copied to the event object, though some of their values may be undefined depending on the event:\r\n\r\n> altKey, bubbles, button, cancelable, charCode, clientX, clientY, ctrlKey, currentTarget, data, detail, eventPhase, metaKey, offsetX, offsetY, originalTarget, pageX, pageY, relatedTarget, screenX, screenY, shiftKey, target, view, which\r\n\r\n`which` property is deprecated by the DOM specification - https://w3c.github.io/uievents/#widl-KeyboardEvent-which, it seems we need to add a note about it (and possible for the other properties too), deprecated it and show message in the migrate?\r\n\r\n/cc @dmethvin \r\n"},"comment":{"url":"https://api.github.com/repos/jquery/jquery/issues/comments/104005926","html_url":"https://github.com/jquery/jquery/issues/2337#issuecomment-104005926","issue_url":"https://api.github.com/repos/jquery/jquery/issues/2337","id":104005926,"user":{"login":"mzgol","id":1758366,"avatar_url":"https://avatars.githubusercontent.com/u/1758366?v=3","gravatar_id":"","url":"https://api.github.com/users/mzgol","html_url":"https://github.com/mzgol","followers_url":"https://api.github.com/users/mzgol/followers","following_url":"https://api.github.com/users/mzgol/following{/other_user}","gists_url":"https://api.github.com/users/mzgol/gists{/gist_id}","starred_url":"https://api.github.com/users/mzgol/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/mzgol/subscriptions","organizations_url":"https://api.github.com/users/mzgol/orgs","repos_url":"https://api.github.com/users/mzgol/repos","events_url":"https://api.github.com/users/mzgol/events{/privacy}","received_events_url":"https://api.github.com/users/mzgol/received_events","type":"User","site_admin":false},"created_at":"2015-05-20T19:27:21Z","updated_at":"2015-05-20T19:27:21Z","body":"The copying already causes performance penalty in Firefox in some cases, see https://github.com/mozilla/treeherder-ui/pull/486 that @fitzgen made me aware of. I didn't have time to measure what's exactly slowing everything down but in the linked PR the jQuery is patched to use getters instead of copying as it significantly speeds up Firefox from what I understand."}}