title: Access to clipboard for Chrome extension using JavaScript
body: <p>I am writing a Chrome Extension. Every time the user copies something, my extension should capture the copied text. 
  I read that access to the clipboard is a security concern. However there is a clipboardRead and clipboardWrite permission according to <a href="https://developer.chrome.com/extensions/declare_permissions" rel="nofollow">https://developer.chrome.com/extensions/declare_permissions</a></p>
  
  <p>Is it possible in any way?</p>