Examine source code of e-Cert Extension

{
  "name": "__MSG_appName__",
  "description": "__MSG_appDesc__",
  "version": "1.0.6",
  "default_locale": "en",
  "permissions": [
    "nativeMessaging"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "16": "images/hkpoca_16.png",
    "32": "images/hkpoca_32.png",
    "64": "images/hkpoca_64.png"
  },
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "hkpo.ecertp.renewal5@hongkongpost.gov.hk",
      "strict_min_version": "50.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.ecert.gov.hk/*",
        "*://*.hongkongpost.gov.hk/*"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ]
}