trying to set window so it has stays on all screens, this is

gistfile1.txt

Cu.import('resource://gre/modules/ctypes.jsm');
var objc = ctypes.open(ctypes.libraryName('objc'));

// BASIC TYPES
var CHAR = ctypes.char;
var ID = ctypes.voidptr_t;
var SEL = ctypes.voidptr_t;
var BOOL = ctypes.signed_char;
var NSUINTEGER = ctypes.unsigned_long;

// COMMON FUNCTIONS
var objc_getClass = objc.declare('objc_getClass', ctypes.default_abi, ID, CHAR.ptr);
var objc_msgSend = objc.declare('objc_msgSend', ctypes.default_abi, ID, ID, SEL, '...');
var sel_registerName = objc.declare('sel_registerName', ctypes.default_abi, SEL, CHAR.ptr);


function getNativeHandlePtrStr(domWindow) {
  const baseWindow = domWindow.QueryInterface(Ci.nsIInterfaceRequestor)
                      .getInterface(Ci.nsIWebNavigation)
                      .QueryInterface(Ci.nsIDocShellTreeItem)
                      .treeOwner
                      .QueryInterface(Ci.nsIInterfaceRequestor)
                      .getInterface(Ci.nsIBaseWindow);
  return baseWindow.nativeHandle;
}

function main() {

  const NSWindowCollectionBehaviorDefault = 0;
  const NSWindowCollectionBehaviorCanJoinAllSpaces = 1 << 0;
  const NSWindowCollectionBehaviorMoveToActiveSpace = 1 << 1;
  const NSWindowCollectionBehaviorManaged = 1 << 2
  const NSWindowCollectionBehaviorTransient = 1 << 3
  const NSWindowCollectionBehaviorStationary = 1 << 4
  const NSWindowCollectionBehaviorParticipatesInCycle = 1 << 5
  const NSWindowCollectionBehaviorIgnoresCycle = 1 << 6
  const NSWindowCollectionBehaviorFullScreenPrimary = 1 << 7
  const NSWindowCollectionBehaviorFullScreenAllowsTiling = 1 << 11
  const NSWindowCollectionBehaviorFullScreenDisallowsTiling = 1 << 12
  
  var winptrstr = getNativeHandlePtrStr(Services.wm.getMostRecentWindow('navigator:browser'));
  var winptr = ctypes.voidptr_t(ctypes.UInt64(winptrstr));


  var collectionBehavior = sel_registerName('collectionBehavior');
  var behavior = objc_msgSend(winptr, collectionBehavior);
  behavior = ctypes.cast(behavior, ctypes.int).value;

  console.log('behavior:', behavior.toString());
  behavior |= NSWindowCollectionBehaviorCanJoinAllSpaces;
  console.log('behavior:', behavior.toString());
  
  var setCollectionBehavior = sel_registerName('setCollectionBehavior:');
  var rez = objc_msgSend(winptr, setCollectionBehavior, ctypes.unsigned_long(behavior));
  console.log('rez:', rez.toString());

  var setLevel = sel_registerName('setLevel:');
  var rez = objc_msgSend(winptr, setLevel, ctypes.unsigned_long(21));
  
}

try {
	main();
} catch(ex) {
	console.error('Exception Occoured:', ex);
}