Examine source code of Das Access extension

{
  "manifest_version": 2,
  "name": "Das Access extension",
  "version": "0.2",
  "description": "Das Access extension",
  "icons": {
    "48": "icons/logo-48.jpg",
    "64": "icons/logo-64.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "nativeextension@dasaccess.com",
      "strict_min_version": "55.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/logo-64.png"
  },
  "permissions": [
    "nativeMessaging"
  ],
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_idle",
      "js": [
        "content-script.js"
      ]
    }
  ]
}