temporary fix for the fullscren patch wich does not apply on the current emacs head (copied from https://github.com/downloads/typester/emacs/feature-fullscreen.patch and modified)

emacs fullscreen patch

diff --git a/lisp/term/ns-win.el b/lisp/term/ns-win.el
index 157b2dd..f3807b7 100644
--- a/lisp/term/ns-win.el
+++ b/lisp/term/ns-win.el
@@ -1263,6 +1263,11 @@ the operating system.")
 (add-to-list 'window-system-initialization-alist '(ns . ns-initialize-window-system))


+(declare-function ns-toggle-fullscreen-internal "nsfns.m" ())
+(defun ns-toggle-fullscreen ()
+  (interactive)
+  (ns-toggle-fullscreen-internal))
+
 (provide 'ns-win)

 ;; arch-tag: eb138a45-4e2e-4d68-b1c9-a39665731644
diff --git a/src/nsfns.m b/src/nsfns.m
index 642ff79..03ffcf7 100644
--- a/src/nsfns.m
+++ b/src/nsfns.m
@@ -2589,6 +2589,34 @@ Value is t if tooltip was open, nil otherwise.  */)

 #endif

+DEFUN ("ns-toggle-fullscreen-internal", Fns_toggle_fullscreen_internal, Sns_toggle_fullscreen_internal,
+       0, 0, 0,
+       doc: /* Toggle fulscreen mode */)
+    ()
+{
+    struct frame *f = SELECTED_FRAME();
+    EmacsWindow *window = ns_get_window(f);
+
+    EmacsWindow *new_window = [window toggleFullscreen];
+    FRAME_NS_WINDOW(f) = new_window;
+
+    NSRect r = [new_window contentRectForFrameRect:[new_window frame]];
+    int cols = FRAME_PIXEL_WIDTH_TO_TEXT_COLS(f, r.size.width);
+    int rows = FRAME_PIXEL_HEIGHT_TO_TEXT_LINES(f, r.size.height);
+
+    change_frame_size (f, rows, cols, 0, 1, 0); /* pretend, delay, safe */
+    FRAME_PIXEL_WIDTH (f) = (int)r.size.width;
+    FRAME_PIXEL_HEIGHT (f) = (int)r.size.height;
+
+    f->border_width = [new_window frame].size.width - r.size.width;
+    FRAME_NS_TITLEBAR_HEIGHT (f) =
+        [new_window frame].size.height - r.size.height;
+
+    [[new_window delegate] windowDidMove:nil];
+
+    return Qnil;
+}
+

 /* ==========================================================================

@@ -2676,6 +2704,8 @@ be used as the image of the icon representing the frame.  */);
   defsubr (&Sx_show_tip);
   defsubr (&Sx_hide_tip);

+  defsubr (&Sns_toggle_fullscreen_internal);
+
   /* used only in fontset.c */
   check_window_system_func = check_ns;

diff --git a/src/nsterm.h b/src/nsterm.h
index 29d312a..17b19e4 100644
--- a/src/nsterm.h
+++ b/src/nsterm.h
@@ -95,8 +95,25 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 {
   NSPoint grabOffset;
 }
+
+-(EmacsWindow *)toggleFullscreen;
+
+@end
+
+/* 10.5 or below is not supported [NSWindow setStyleMask:], so require content swap hack */
+@interface EmacsFullWindow : EmacsWindow {
+    EmacsWindow *normalWindow;
+}
+
+-(id)initWithNormalWindow:(EmacsWindow *)window;
+-(EmacsWindow *)getNormalWindow;
+
 @end

+// dummy for 10.5-
+#define NSApplicationPresentationDefault 0
+#define NSApplicationPresentationAutoHideDock (1 <<  0)
+#define NSApplicationPresentationAutoHideMenuBar (1 <<  2)

 /* ==========================================================================

diff --git a/src/nsterm.m b/src/nsterm.m
index 9256c08..8bbb575 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -686,6 +686,13 @@ ns_focus (struct frame *f, NSRect *r, int n)
 /*debug_lock--; */
             }

+          if (view) {
+              EmacsFullWindow *win = [view window];
+              if ([win isKindOfClass:[EmacsFullWindow class]]) {
+                  [[win getNormalWindow] orderOut:nil];
+              }
+          }
+
           if (view)
 #ifdef NS_IMPL_GNUSTEP
             r ? [view lockFocusInRect: u] : [view lockFocus];
@@ -1131,8 +1138,14 @@ x_set_window_size (struct frame *f, int change_grav, int cols, int rows)
   f->scroll_bar_actual_width = NS_SCROLL_BAR_WIDTH (f);
   compute_fringe_widths (f, 0);

-  pixelwidth =  FRAME_TEXT_COLS_TO_PIXEL_WIDTH   (f, cols);
-  pixelheight = FRAME_TEXT_LINES_TO_PIXEL_HEIGHT (f, rows);
+  if ([window isKindOfClass:[EmacsFullWindow class]]) {
+      pixelwidth = [[window screen] frame].size.width;
+      pixelheight = [[window screen] frame].size.height;
+  }
+  else {
+      pixelwidth =  FRAME_TEXT_COLS_TO_PIXEL_WIDTH   (f, cols);
+      pixelheight = FRAME_TEXT_LINES_TO_PIXEL_HEIGHT (f, rows);
+  }

   /* If we have a toolbar, take its height into account. */
   if (tb)
@@ -1197,7 +1210,7 @@ x_set_window_size (struct frame *f, int change_grav, int cols, int rows)
   change_frame_size (f, rows, cols, 0, 1, 0); /* pretend, delay, safe */
   FRAME_PIXEL_WIDTH (f) = pixelwidth;
   FRAME_PIXEL_HEIGHT (f) = pixelheight;
-/*  SET_FRAME_GARBAGED (f); // this short-circuits expose call in drawRect */
+  /*  SET_FRAME_GARBAGED (f); // this short-circuits expose call in drawRect */

   mark_window_cursors_off (XWINDOW (f->root_window));
   cancel_mouse_face (f);
@@ -5609,6 +5622,59 @@ extern void update_window_cursor (struct window *w, int on);

 @implementation EmacsWindow

+-(NSWindow *)toggleFullscreen {
+    BOOL isFullscreen = [[self className] isEqualToString:@"EmacsFullWindow"];
+    NSWindow *win;
+
+    if (isFullscreen) {
+        EmacsFullWindow *f = (EmacsFullWindow *)self;
+        EmacsWindow *w = [f getNormalWindow];
+
+        [w setContentView:[f contentView]];
+        [w makeKeyAndOrderFront:nil];
+
+        [f close];
+
+        win = w;
+
+        if ([[self screen] isEqual:[[NSScreen screens] objectAtIndex:0]]) {
+            if ([NSApp respondsToSelector:@selector(setPresentationOptions:)]) {
+                [NSApp setPresentationOptions:NSApplicationPresentationDefault];
+            }
+            else {
+                [NSMenu setMenuBarVisible:YES];
+            }
+        }
+    }
+    else {
+        [self deminiaturize:nil];
+
+        if ([[self screen] isEqual:[[NSScreen screens] objectAtIndex:0]]) {
+            if ([NSApp respondsToSelector:@selector(setPresentationOptions:)]) {
+                [NSApp setPresentationOptions:NSApplicationPresentationAutoHideDock | NSApplicationPresentationAutoHideMenuBar];
+            }
+            else {
+                [NSMenu setMenuBarVisible:NO];
+            }
+        }
+
+        [self orderOut:nil];
+
+        EmacsFullWindow *f = [[EmacsFullWindow alloc] initWithNormalWindow:self];
+        EmacsView *view = (EmacsView *)[self delegate];
+        [f setDelegate:view];
+        [f makeFirstResponder:view];
+        [f setContentView:[self contentView]];
+        [f setContentSize:[[self screen] frame].size];
+        [f setTitle:[self title]];
+        [f makeKeyAndOrderFront:nil];
+
+        win = f;
+    }
+
+    return win;
+}
+
 /* called only on resize clicks by special case in EmacsApp-sendEvent */
 - (void)mouseDown: (NSEvent *)theEvent
 {
@@ -5667,6 +5733,32 @@ extern void update_window_cursor (struct window *w, int on);

 @end /* EmacsWindow */

+@implementation EmacsFullWindow
+
+-(BOOL)canBecomeKeyWindow {
+    return YES;
+}
+
+-(id)initWithNormalWindow:(EmacsWindow *)window {
+    self = [super initWithContentRect:[window contentRectForFrameRect:[[window screen] frame]]
+                            styleMask:NSBorderlessWindowMask
+                              backing:NSBackingStoreBuffered
+                                defer:YES];
+    if (self) {
+        normalWindow = window;
+        [self setAcceptsMouseMovedEvents: YES];
+        [self useOptimizedDrawing: YES];
+    }
+
+    return self;
+}
+
+-(EmacsWindow *)getNormalWindow {
+    return normalWindow;
+}
+
+@end /* EmacsFullWindow */
+

 /* ==========================================================================