Examine source code of Cloud CRM Extension

{
  "description": "Cloud CRM Extension",
  "manifest_version": 2,
  "name": "Cloud CRM Extension",
  "version": "1.5",
  "applications": {
    "gecko": {
      "id": "com.commsl.browser_extension_firefox@commsl.com.br",
      "strict_min_version": "55.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/message.svg"
  },
  "permissions": [
    "nativeMessaging"
  ]
}