Rewrites silently modify query string when "=" is ... Create a rewrite in next.config.js with some path as the source and the url of the request bin you created as the destination. E.g. {source: ...

The Envoy access_log documentation has an example with REQ(X-ENVOY-ORIGINAL-PATH?:PATH) for logging the request's path, but both the :PATH and X-ENVOY-ORIGINAL-PATH header contain the query string..