Examine source code of Scratch Share

{
  "manifest_version": 2,
  "name": "ScratchShare",
  "version": "1.1.0",
  "description": "Share Scratch projects on social media with ease.",
  "icons": {
    "48": "Images/icons/icon-48.png",
    "96": "Images/icons/icon-96.png"
  },
  "browser_action": {
    "default_icon": {
      "48": "Images/icons/icon-48.png",
      "96": "Images/icons/icon-96.png"
    },
    "default_title": "ScratchShare",
    "default_popup": "popup.html"
  },
  "permissions": [
    "activeTab",
    "storage",
    "https://scratch.mit.edu/*/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{595b9fea-d077-49b2-b8fc-7afe7f1f369e}"
    }
  }
}