# Cross-site scripting Protection (X-XSS-Protection header)

{% hint style="warning" %}
This header is non-standard and should not be used. Instead, it is recommended to use a [Content Security Policy (CSP)](/umbraco-cms/extending/health-check/guides/contentsecuritypolicy.md) header.

For more information about the X-XSS-Protection header, and why it should not be used, see [MDN web docs](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-XSS-Protection).
{% endhint %}

## How to fix this health check

This health check can be fixed by ensuring no middleware adds the header.


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# Agent Instructions: Querying This Documentation

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
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```

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Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.