Examine source code of Statusbrew

{
  "name": "__MSG_extLangName__",
  "description": "__MSG_extLangDesc__",
  "default_locale":"en",
  "version": "3.1.3",
  "manifest_version": 2,
  "homepage_url": "http://statusbrew.com",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "background": {
    "scripts": [
      "event.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/icon16.png",
    "default_title": "Statusbrew"
    // "default_popup": "popup.html"
  },
  "permissions": [
    "clipboardRead",
    "clipboardWrite",
    "contextMenus",
    "history",
    "idle",
    "management",
    "notifications",
    "storage",
    "tabs",
    "https://*/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*/*",
        "http://*/*"
      ],
      "js": [
        "content.js"
      ],
      "css": ["content.css"]
    }
  ]
}