XmVaCreateMessageBox(3) on Linux
The text e679ff5ffb04, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A MessageBox widget convenience creation functions. "XmVaCreateToggleMessageBox" "XmVaCreateManagedMessageBox" "creation functions" "XmVaCreateMessageBox"