Examine source code of HTTP Version Indicator

{
  "manifest_version": 2,
  "name": "__MSG_extension_name__",
  "version": "2",
  "description": "__MSG_extension_description__",
  "default_locale": "en",
  "icons": {
    "1": "Icons/HTTP%20Version%20Indicator%20Icon.svg"
  },
  "applications": {
    "gecko": {
      "id": "http.version.indicator@patrick.dark.name"
    }
  },
  "permissions": [
    "http://*/*",
    "https://*/*",
    "webRequest"
  ],
  "page_action": {
    "browser_style": false
  },
  "background": {
    "scripts": [
      "HTTP%20Version%20Indicator%20Background%20Script.js"
    ]
  }
}