Examine source code of Hostname in Window Title

{
  "manifest_version": 2,
  "name": "Hostname in Window Title",
  "version": "2.3resigned1",
  "description": "Adds the hostname of windows' active tab to the windows' title, e.g. for KeePass(X/XC).",
  "developer": {
    "name": "Aaron Papp",
    "url": "https://github.com/Aaron-P/HostnameTitleBar"
  },
  "icons": {
    "24": "icon.svg",
    "32": "icon.svg",
    "48": "icon.svg",
    "64": "icon.svg",
    "96": "icon.svg"
  },
  "applications": {
    "gecko": {
      "strict_min_version": "57.0",
      "id": "{eb5a5a3a-b3e7-447c-8e5b-b4b20ae03876}"
    }
  },
  "permissions": [
    "*://*/*",
    "storage",
    "tabs"
  ],
  "options_ui": {
    "browser_style": true,
    "page": "options.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ]
}