XmCreateMessageBox(3) on Linux
The text 6ff7ef6d84e1, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
The MessageBox widget creation function "XmCreateMessageBox" "creation functions" "XmCreateMessageBox"