Examine source code of ASCII Table

{
  "manifest_version": 3,
  "name": "ASCII",
  "version": "1.0",
  "description": "Displays an ASCII table on click",
  "action": {
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "Benes@iwp.edu"
    }
  }
}