Examine source code of Vivir

{
  "manifest_version": 2,
  "name": "Vivir",
  "version": "1.2.3resigned1",
  "short_name": "Vivir",
  "description": "Vivir: new tab with a new Spanish word.",
  "icons": {
    "128": "icon_128.png"
  },
  "author": "Rasmus Johanson",
  "homepage_url": "https://gitlab.com/rasmus/vivir",
  "minimum_chrome_version": "55",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "options_ui": {
    "page": "settings.html",
    "chrome_style": true
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{8a543f0f-7e1f-4f89-ac68-d7630ceeb3b5}"
    }
  }
}