Examine source code of Open Graph Previewer

{
  "description": "Preview how your website looks on social media with every Open Graph configuration, instantly.",
  "manifest_version": 2,
  "name": "Open Graph Previewer",
  "version": "1.0.1",
  "author": "Ruben Winant",
  "icons": {
    "48": "icons/eye.png"
  },
  "background": {
    "scripts": [
      "/background.js"
    ]
  },
  "permissions": [
    "tabs",
    "activeTab",
    "storage",
    "webNavigation"
  ],
  "devtools_page": "devtools/devtools-page.html",
  "browser_action": {
    "default_title": "Open Graph Previewer",
    "default_popup": "popup/info.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "ruben.winant@hotmail.com",
      "strict_min_version": "57.0"
    }
  },
  "developer": {
    "name": "Ruben Winant",
    "url": "https://www.rubenwinant.be"
  }
}