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Network Error Logging (NEL)

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Network Error Logging is a mechanism that can be configured via the NEL HTTP response header. This experimental header allows websites and applications to opt-in to receive reports about failed (and, if desired, successful) network fetches from supporting browsers.

Reports are sent to a reporting group defined within a Report-To header.

Usage

Web applications opt in to this behavior with the NEL header, which is a JSON-encoded object:

http
NEL: { "report_to": "nel",
       "max_age": 31556952 }

An origin considered secure by the browser is required.

The following object keys can be specified in the NEL header:

report_to

The reporting API group to send network error reports to (see below).