By combining the powers of real-user experiences in the Chrome UX Report 26 (CrUX) dataset with web technology detections in HTTP Archive 30, we can get a glimpse into how architectural decisions like choices of CMS platform or JavaScript framework play a role in sites’ CWV performance.

They use a tool called wappalyzer to identify what technologies a given website is using by looking for certain scripts, global JS variables, or other identifying characteristics. For example, for Remix applications, they look for the global __remixContext variable to identify that a website is using Remix.

It was brought to our attention that React Router was unable to be reliably identified because there are no identifying global aspects. They are currently looking for external scripts with react-router in the name. This will identify sites using React Router from a CDN such as unpkg - but it will miss the vast majority of sites that are installing React Router from the npm registry and bundling it into their JS files. This results in drastically under-reporting the usage of React Router on the web.

Starting with version 6.22.0, sites using react-router-dom will begin adding a window.__reactRouterVersion variable that will be set to a string value of the SemVer major version number (i.e., window.__reactRouterVersion = "6";) so that they can be properly identified.

Minor Changes

Include a window.__reactRouterVersion for CWV Report detection (#11222)
Add a createStaticHandler future.v7_throwAbortReason flag to throw request.signal.reason (defaults to a DOMException) when a request is aborted instead of an Error such as new Error("query() call aborted: GET /path") (#11104)
- Please note that DOMException was added in Node v17 so you will not get a DOMException on Node 16 and below.