Favicon Monitor

Reports the presence of favicons on page-load, and optionally when they change.

Notifications

faviconFound

• "Favicon Messages".FaviconFoundNotification
• Sent on page load, sends "Favicon Messages".FaviconFound

Example

{
    "favicons": [
        {
            "href": "favicon.png",
            "rel": "stylesheet"
        }
    ],
    "documentUrl": "https://example.com"
}
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Remote Config

Enabled (default)

{
  "features": {
    "favicon": {
      "state": "enabled",
      "exceptions": [],
      "settings": {
        "monitor": true
      }
    }
  },
  "unprotectedTemporary": []
}
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Disable the monitor only.

To only receive the initial payload and nothing more (to mimic the old behavior), you can set monitor: false in the remote config, and it will not install the Mutation Observer.

{
  "features": {
    "favicon": {
      "state": "enabled",
      "exceptions": [],
      "settings": {
        "monitor": false
      }
    }
  },
  "unprotectedTemporary": []
}
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