Examine source code of What Reddit Says

{
  "manifest_version": 3,
  "name": "What Reddit Says",
  "version": "0.1.0",
  "description": "Easily find Reddit discussions about the page you're currently browsing.",
  "homepage_url": "https://github.com/kiliankoe/what-reddit-says",
  "browser_specific_settings": {
    "gecko": {
      "id": "what-reddit-says@kiliankoe.github.io"
    }
  },
  "icons": {
    "16": "assets/icon-16.png",
    "32": "assets/icon-32.png",
    "48": "assets/icon-48.png",
    "96": "assets/icon-96.png",
    "128": "assets/icon-128.png",
    "256": "assets/icon-256.png"
  },
  "permissions": [
    "activeTab"
  ],
  "host_permissions": [
    "https://www.reddit.com/*",
    "https://old.reddit.com/*"
  ],
  "action": {
    "default_icon": {
      "16": "assets/icon-16.png",
      "32": "assets/icon-32.png",
      "48": "assets/icon-48.png"
    },
    "default_title": "Click to find what Reddit says",
    "default_popup": "popup.html"
  }
}