Simple JSX Viewer

A clean, secure Chrome extension for previewing JSX components.

We built this because the existing JSX preview extensions are either abandoned, request unnecessary permissions, or load code from third-party CDNs you can’t audit. We wanted one that does the job without any of that.

This extension is fully offline, fully open-source, and requests zero permissions.

Install

1. Clone this repo
2. Go to chrome://extensions in Chrome
3. Enable Developer mode
4. Click Load unpacked and select the folder

How it works

Load a .jsx file — via file picker, drag-and-drop, or a raw URL — and it renders instantly in a sandboxed iframe. That’s it.

• JSX is transpiled locally using Sucrase
• Components render with React 18, bundled in the extension
• User code never touches the extension context

Security

• No permissions — the manifest requests nothing
• No CDN calls — React, ReactDOM, Sucrase, and fonts are all bundled locally
• Sandboxed iframe — rendered components are isolated from the extension and your browser
• No background activity — the service worker only opens a tab when you click the icon
• Auditable — the entire extension is ~700KB of readable source and standard libraries

The only network request this extension ever makes is when you paste a URL and click Load.

Bundled versions

React 18.3.1, ReactDOM 18.3.1, Sucrase 3.35.1. See VERSIONS.md for details.

License

MIT — see LICENSE.

Built by keepsimple.io.