Gtk.Scale.prototype.set_has_origin

function set_has_origin(has_origin:Boolean):void {
    // Gjs wrapper for gtk_scale_set_has_origin()
}

If has_origin is set to true (the default), the scale will highlight the part of the scale between the origin (bottom or left side) of the scale and the current value.

Since 3.4

has_origin

true if the scale has an origin