navigator.keyboard.lock Polyfill

A tiny polyfill for Chromium’s navigator.keyboard.lock() API.

• Chromium API: https://wicg.github.io/keyboard-lock/
• Standard API: https://fullscreen.spec.whatwg.org/#keyboard-lock

What it does

Maps navigator.keyboard.lock() / unlock() to the standardized Fullscreen keyboard lock (requestFullscreen({ keyboardLock })).

Limitations

This script only affects the current document. The keyboard lock state is not passed down to child documents that call requestFullscreen().

The script tries to support any order of calling requestFullscreen() and navigator.keyboard.lock(). It thus fakes a fullscreenchange event, and actually goes fullscreen later (which will fire another fullscreenchange event).

The recommended order is navigator.keyboard.lock() first, then requestFullscreen().

Security

This package is a browser-only polyfill. It intentionally patches Element.prototype.requestFullscreen, navigator.keyboard, and Permissions.prototype.query to emulate Chromium's Keyboard Lock API.

It has no dependencies and performs no network requests.

Browser support

Works in browsers that support the standard API:

• Safari 26.4+
• Firefox 151+

Usage

<script src="index.js"></script>

See demo.

npm

This polyfill is available on NPM.

npm install navigator-keyboard-lock-polyfill

import "navigator-keyboard-lock-polyfill";

License

MIT