CURLINFO_REFERER(3) on macOS
The text 4129296864e0, as macOS 26.5, macOS 26.4, macOS 26.3, macOS 26.2, macOS 26.1, macOS 26.0, macOS 15.6, macOS 15.5, macOS 15.4, macOS 15.3, macOS 15.2, macOS 15.1, macOS 15.0, macOS 14.6, macOS 14.5 shipped it. The page shows this text now.
get the used referrer request header