Examine source code of Insertly - Template Manager

{
  "manifest_version": 2,
  "name": "Insertly - Template Manager",
  "version": "1.1.1",
  "description": "Offline template manager with dynamic variables. Create templates once, insert anywhere on the web—no internet required.",
  "permissions": [
    "contextMenus",
    "storage",
    "tabs",
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "insertly@extension",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "browser_action": {
    "default_popup": "src/popup/popup.html",
    "default_title": "Insertly - Template Manager"
  },
  "background": {
    "scripts": [
      "src/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "src/insertion.js",
        "src/content-script.js"
      ],
      "run_at": "document_end",
      "all_frames": true
    }
  ],
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  }
}