Examine source code of fxclipboard

{
  "manifest_version": 2,
  "name": "fxclipboard",
  "author": "rtldg",
  "version": "2.1",
  "description": "Rewrite things in your clipboard, like domains, maybe with regex",
  "homepage_url": "https://github.com/rtldg/fxclipboard",
  "icons": {
    "48": "icons/fxclipboard48.png",
    "96": "icons/fxclipboard96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{846f05b8-874e-422d-b688-24f84e124e5d}",
      "strict_min_version": "128.0"
    }
  },
  "permissions": [
    "storage",
    "clipboardRead",
    "clipboardWrite"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}