{"action":"created","issue":{"url":"https://api.github.com/repos/Polymer/polymer/issues/3463","repository_url":"https://api.github.com/repos/Polymer/polymer","labels_url":"https://api.github.com/repos/Polymer/polymer/issues/3463/labels{/name}","comments_url":"https://api.github.com/repos/Polymer/polymer/issues/3463/comments","events_url":"https://api.github.com/repos/Polymer/polymer/issues/3463/events","html_url":"https://github.com/Polymer/polymer/issues/3463","id":136019257,"number":3463,"title":"Cloning custom-element including <content> duplicates its nodes?","user":{"login":"xliiv","id":298994,"avatar_url":"https://avatars.githubusercontent.com/u/298994?v=3","gravatar_id":"","url":"https://api.github.com/users/xliiv","html_url":"https://github.com/xliiv","followers_url":"https://api.github.com/users/xliiv/followers","following_url":"https://api.github.com/users/xliiv/following{/other_user}","gists_url":"https://api.github.com/users/xliiv/gists{/gist_id}","starred_url":"https://api.github.com/users/xliiv/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/xliiv/subscriptions","organizations_url":"https://api.github.com/users/xliiv/orgs","repos_url":"https://api.github.com/users/xliiv/repos","events_url":"https://api.github.com/users/xliiv/events{/privacy}","received_events_url":"https://api.github.com/users/xliiv/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":1,"created_at":"2016-02-24T10:31:09Z","updated_at":"2016-02-24T18:50:13Z","closed_at":null,"body":"<!-- Instructions: https://github.com/Polymer/polymer/blob/master/CONTRIBUTING.md#filing-bugs -->\r\n### Description\r\n<!-- Example: Error thrown when calling `appendChild` on Polymer element -->\r\nElement child are duplicated when ```<content></content>``` is included.\r\n\r\n#### Live Demo\r\nhttp://jsbin.com/selikifeja/1/edit?html,console,output\r\n\r\n#### Steps to Reproduce\r\n<!--\r\nExample:\r\n\r\n1. Create `my-element`\r\n2. Append `my-element to document.body\r\n3. Create `div`.\r\n4. Append `div` to `my-element`\r\n-->\r\n1. Click on trigger button http://jsbin.com/selikifeja/1/edit?html,console,output\r\n\r\n\r\n\r\n#### Expected Results\r\nCloned element has the same content as cloning element.\r\n\r\n#### Actual Results\r\n<!-- Example: Error is thrown -->\r\n```<h2>Before</h2>``` and ```<h2>After</h2>``` are duplicated\r\n\r\n### Browsers Affected\r\n<!-- Check all that apply -->\r\n- [x ] Chrome\r\n- [x ] Firefox\r\n- [ ] Edge ?\r\n- [ ] Safari 9 ?\r\n- [ ] Safari 8 ?\r\n- [ ] IE 11 ?\r\n\r\n### Versions\r\n<!--\r\n`Polymer.version` will show the version for Polymer\r\n`bower ls` or `npm ls` will show the version of webcomponents.js or webcomponents-lite.js\r\n-->\r\n- Polymer: v1.2.4\r\n- webcomponents: v0.7.21 \r\n"},"comment":{"url":"https://api.github.com/repos/Polymer/polymer/issues/comments/188402960","html_url":"https://github.com/Polymer/polymer/issues/3463#issuecomment-188402960","issue_url":"https://api.github.com/repos/Polymer/polymer/issues/3463","id":188402960,"user":{"login":"sorvell","id":78891,"avatar_url":"https://avatars.githubusercontent.com/u/78891?v=3","gravatar_id":"","url":"https://api.github.com/users/sorvell","html_url":"https://github.com/sorvell","followers_url":"https://api.github.com/users/sorvell/followers","following_url":"https://api.github.com/users/sorvell/following{/other_user}","gists_url":"https://api.github.com/users/sorvell/gists{/gist_id}","starred_url":"https://api.github.com/users/sorvell/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/sorvell/subscriptions","organizations_url":"https://api.github.com/users/sorvell/orgs","repos_url":"https://api.github.com/users/sorvell/repos","events_url":"https://api.github.com/users/sorvell/events{/privacy}","received_events_url":"https://api.github.com/users/sorvell/received_events","type":"User","site_admin":false},"created_at":"2016-02-24T18:50:13Z","updated_at":"2016-02-24T18:50:13Z","body":"You'll need to clone the element using Polymer's `Polymer.dom` api to be compatible with both native Shadow DOM and Polymer's Shady DOM shim.\r\n\r\nHere's a link to the docs about this: https://www.polymer-project.org/1.0/docs/devguide/local-dom.html#dom-api.\r\n\r\nHere's a working example: http://jsbin.com/lujipax/1/edit?html,output"}}