Examine source code of Microsoft WowTab

{
  "version": "1.3.177",
  "version_name": "1.3.177-WOWT00",
  "short_name": "Microsoft WowTab",
  "description": "__MSG_Description__",
  "name": "Microsoft WowTab",
  "manifest_version": 3,
  "default_locale": "en",
  "install_id": "__INSTALLID__",
  "browser_specific_settings": {
    "gecko": {
      "id": "v-guanyuan@microsoft.com",
      "strict_min_version": "58.0"
    }
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "chrome_settings_overrides": {
    "homepage": "index.html",
    "search_provider": {
      "name": "Bing",
      "favicon_url": "favicon.ico",
      "is_default": true,
      "prepopulated_id": 3,
      "search_url": "https://www.bing.com/search?form=WOWTSE&pc=WOWT00&q={searchTerms}",
      "suggest_url": "https://www.bing.com/osjson.aspx?form=WOWTSE&pc=WOWT00&query={searchTerms}"
    }
  },
  "host_permissions": [
    "*://*/*"
  ],
  "action": {
    "default_icon": {
      "16": "icons/logo16.png",
      "32": "icons/logo32.png"
    }
  },
  "icons": {
    "16": "icons/logo16.png",
    "32": "icons/logo32.png",
    "48": "icons/logo48.png",
    "128": "icons/logo128.png"
  },
  "permissions": [
    "offscreen",
    "storage",
    "cookies",
    "alarms"
  ],
  "optional_permissions": [
    "bookmarks",
    "favicon"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "_favicon/*"
      ],
      "matches": [
        "<all_urls>"
      ],
      "extension_ids": [
        "*"
      ]
    }
  ],
  "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA4cYoIR1q6zRLLstMYNMvWLhId4hEWiCGAtavo6aimxrSagOiVACAEAV5liWRrTpH0l9YkB/Ky4Bshcg80+MkRf4dW8ldng4wovwsc5/CU0Hf7+HMwv6IDqlLIPo8/pAAWyc2SIAd4rHsyZFXo6OBN7HNOYTWhEYLGlLtly2T0fc7LVNENTdXoQMl65jeohh5OSmnXZznCj6UgyKi/+5pc9NJVxPuH+ziXvfixT7t01ZKP5P3GQY8Cdy7OGrAO+NP0qNLuuKRVOEmh6yHuxZZUsveBYXZ2XDXbQ7bHN1SCnxC9necgcMXDvzjOemaQWg1fQo1Klwt6tKXIN+wE+wo5QIDAQAB"
}