Below is the code I am trying (plus a few variations), there is a dialog asking for my permission, but still errors out with
Error: Permission denied for to get property XPCComponents.classes
unsafeWindow.netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
var file = unsafeWindow.Components.classes["@mozilla.org/file/local;1"]
.createInstance(Components.interfaces.nsILocalFile);
file.initWithPath("d:\\test.bat");
var process = unsafeWindow.Components.classes["@mozilla.org/process/util;1"]
.createInstance(Components.interfaces.nsIProcess);
process.init(file);
var args = ["argument1", "argument2"];
process.run(false, args, args.length);
Is this just going to be impossible?