# Crossbench Proxy extension: Custom replay button in DevTools > Recorder

This extension is using the [chrome.devtools.recorder API](https://developer.chrome.com/docs/extensions/reference/devtools_recorder/).

To test the extension:

1. Download this directory to your machine: `git clone https://chromium.googlesource.com/crossbench`.
2. [Load the extension locally](https://developer.chrome.com/docs/extensions/mv3/getstarted/development-basics/#load-unpacked).
3. Open a new tab and a new DevTools window.
4. In the **Recorder** panel, create a new recording.
5. Expand the replay menu and press **crossbench**.