Where it says about a pg down
https://duet3d.dozuki.com/Wiki/Gcode#Section_Replies_from_the_RepRap_machine_to_the_host_computer
"On the latest version of Pronterface and Octoprint (1.2.0+) a special comment of the form:
// action:command
is allowed to be sent from the firmware, the command can currently be pause, resume or disconnect which will execute those commands on the host."
Is this referring to a release candidate or beta version?
I'm on the latest stable version and either I don't know how to trigger one or it is not in this version.