Examine source code of PasteMate

{
  "manifest_version": 2,
  "name": "PasteMate",
  "description": "Smart clipboard manager to access your recent copied text.",
  "version": "1.0.2",
  "permissions": [
    "clipboardRead",
    "clipboardWrite",
    "storage",
    "activeTab",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+V"
      },
      "description": "Open PasteMate popup"
    }
  },
  "applications": {
    "gecko": {
      "id": "pastemate@yourdomain.com",
      "strict_min_version": "58.0"
    }
  }
}