XmRemoveWMProtocols(3) on Linux
The text 34ef3b8b7df2, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A VendorShell convenience interface that removes the protocols from the protocol manager and deallocates the internal tables "XmRemoveWMProtocols" "VendorShell functions" "XmRemoveWMProtocols" "protocols"