form_userptr(3x) on macOS
The text bfcca178a66a, 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, macOS 14.4, macOS 14.3, macOS 14.2, macOS 14.1, macOS 14.0 shipped it. The page shows this text now.
associate application data with a form item