Examine source code of Stack Copy Button

{
  "manifest_version" : 2 ,
  "name" : "Stack Copy Button",
  "author": "MrMino",
  "description" : "A copy button for Stack Overflow code boxes",
  "version" : "1.1.3resigned1",
  "browser_action" : {
    "default_icon" : "icon32.png"
  },
  "icons" : {
    "32" : "icon32.png",
    "128" : "icon128.png"
  },
  "permissions" : [
    "*://stackoverflow.com/*" ,
    "clipboardWrite" 
  ],
  "content_scripts" : [
    {
      "matches" : [
        "*://*.stackoverflow.com/*" 
      ],
      "js" : [
        "jquery-1.12.3.min.js" ,
        "copybox.min.js" 
      ]
    }
  ],
  "applications": {
    "gecko": {
      "id": "stack.copy.button@mr.mino"
    }
  }
}