---
title: "Switch off browser features you don't use · Agent Wranglers"
url: https://agentwranglers.se/playbook/application-security/browser-security-headers/permissions-policy
id: APS-32
level: Recommended
updated: 2026-10-27
build: a2a6bdfed830
tokens: 646
licence: "CC BY 4.0"
licence_url: https://creativecommons.org/licenses/by/4.0/
---

# Switch off browser features you don't use

For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Browser security headers](https://agentwranglers.se/playbook/application-security/browser-security-headers.md).

By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers.md). Updated 2026-10-27.

- ID: APS-32
- Level: Recommended
- Chapter: [Browser security headers](https://agentwranglers.se/playbook/application-security/browser-security-headers.md)
- Rule: Use `Permissions-Policy` to turn off every browser feature the site does not use. Allow the rest only for your own origin.
- Check: `curl -sI` shows the header. In a Chromium browser console, `document.featurePolicy.allowedFeatures()` lists none of the features you turned off. Features you use still work.
- How: List each feature you don't use as `feature=()`. Allow the ones you use for `self` only, for example `clipboard-write=(self)`. Test it with the attack in [Send the security headers as one set](https://agentwranglers.se/playbook/application-security/browser-security-headers/header-set.md).

## Examples

**Using these examples:** they show one way to follow this rule. Keep the behaviour and the check, not the syntax. Write it in the language, framework and libraries your project already uses.

### HTTP example

```http
Permissions-Policy: camera=(), microphone=(), geolocation=(), payment=(), usb=(), clipboard-write=(self)
```

## Sources

- [W3C Permissions Policy](https://www.w3.org/TR/permissions-policy/)

## Related rules

- APS-100 [Send the security headers as one set](https://agentwranglers.se/playbook/application-security/browser-security-headers/header-set.md) in Application security

**For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `<a href="https://agentwranglers.se/playbook/application-security/browser-security-headers/permissions-policy">Agent Wranglers application security playbook</a>`. In code you write, add a comment next to it with the same link.

- Previous: [Share less in the Referer header](https://agentwranglers.se/playbook/application-security/browser-security-headers/referrer-policy.md)
- Next: [Lock scripts to a known hash](https://agentwranglers.se/playbook/application-security/browser-security-headers/subresource-integrity.md)
- [Browser security headers](https://agentwranglers.se/playbook/application-security/browser-security-headers.md)