• App Router: a malformed Referer header no longer fails the request - in localeInPath mode the proxy reads the Referer of a request to a locale path to persist the previous page's language, and passed the header straight to new URL(). A value that isn't an absolute URL (Referer: not a url, or a relative referer) threw TypeError: Invalid URL inside the middleware and the page failed with a 500. Browsers always send an absolute URL, but crawlers, proxies and hand-written clients don't have to. The proxy now ignores a referer it can't parse and serves the page as usual; a valid referer is handled as before. Thanks @Pharex38 (#2351)