Examine source code of Clipboard Manager

{
  "manifest_version": 2,
  "name": "Clipboard Manager",
  "version": "1.0",
  "description": "Save and manage multiple clipboard entries.",
  "applications": {
    "gecko": {
      "id": "{547d581c-955e-4950-b758-9e86152358c3}",
      "strict_min_version": "109.0"
    }
  },
  "permissions": [
    "storage",
    "clipboardWrite"
  ],
  "browser_action": {
    "default_title": "Clipboard Manager",
    "default_popup": "popup.html"
  },
  "icons": {
    "48": "icon48.png"
  }
}