Examine source code of OpenFileEditor

{
  "manifest_version": 2,
  "name": "OpenFileEditor",
  "description": "Open any file in your favourite text editor from any web page.",
  "version": "1.1.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "openfileeditor@luigifab.fr",
      "strict_min_version": "58.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "permissions": [
    "nativeMessaging",
    "activeTab"
  ]
}