diff --git a/app/internal/wm/os_macos.go b/app/internal/wm/os_macos.go
index d088a924..b9266d83 100644
--- a/app/internal/wm/os_macos.go
+++ b/app/internal/wm/os_macos.go
@@ -172,11 +172,10 @@ func (w *window) Option(opts *Options) {
 func (w *window) SetWindowMode(mode WindowMode) {
 	switch mode {
 	case w.mode:
-		return
-	case Fullscreen:
+	case Windowed, Fullscreen:
 		C.gio_toggleFullScreen(w.window)
+		w.mode = mode
 	}
-	w.mode = mode
 }
 
 func (w *window) SetCursor(name pointer.CursorName) {
diff --git a/app/internal/wm/os_wayland.go b/app/internal/wm/os_wayland.go
index 1e8c59d9..03790959 100644
--- a/app/internal/wm/os_wayland.go
+++ b/app/internal/wm/os_wayland.go
@@ -181,6 +181,7 @@ type window struct {
 
 	mu        sync.Mutex
 	animating bool
+	opts      *Options
 	needAck   bool
 	// The most recent configure serial waiting to be ack'ed.
 	serial   C.uint32_t
@@ -357,7 +358,7 @@ func (d *wlDisplay) createNativeWindow(opts *Options) (*window, error) {
 	C.xdg_surface_add_listener(w.wmSurf, &C.gio_xdg_surface_listener, unsafe.Pointer(w.surf))
 	C.xdg_toplevel_add_listener(w.topLvl, &C.gio_xdg_toplevel_listener, unsafe.Pointer(w.surf))
 
-	w.Option(opts)
+	w.setOptions(opts)
 
 	if d.decor != nil {
 		// Request server side decorations.
@@ -910,6 +911,13 @@ func (w *window) WriteClipboard(s string) {
 }
 
 func (w *window) Option(opts *Options) {
+	w.mu.Lock()
+	w.opts = opts
+	w.mu.Unlock()
+	w.disp.wakeup()
+}
+
+func (w *window) setOptions(opts *Options) {
 	_, _, cfg := w.config()
 	if o := opts.Size; o != nil {
 		w.width = cfg.Px(o.Width)
@@ -1143,8 +1151,10 @@ func (w *window) process() {
 	w.mu.Lock()
 	readClipboard := w.readClipboard
 	writeClipboard := w.writeClipboard
+	opts := w.opts
 	w.readClipboard = false
 	w.writeClipboard = nil
+	w.opts = nil
 	w.mu.Unlock()
 	if readClipboard {
 		r, err := w.disp.readClipboard()
@@ -1163,6 +1173,9 @@ func (w *window) process() {
 	if writeClipboard != nil {
 		w.disp.writeClipboard([]byte(*writeClipboard))
 	}
+	if opts != nil {
+		w.setOptions(opts)
+	}
 	// pass false to skip unnecessary drawing.
 	w.draw(false)
 }
diff --git a/app/internal/wm/os_windows.go b/app/internal/wm/os_windows.go
index 611c7cb0..05d440ea 100644
--- a/app/internal/wm/os_windows.go
+++ b/app/internal/wm/os_windows.go
@@ -66,6 +66,7 @@ type window struct {
 const (
 	_WM_REDRAW = windows.WM_USER + iota
 	_WM_CURSOR
+	_WM_OPTION
 )
 
 type gpuAPI struct {
@@ -317,6 +318,8 @@ func windowProc(hwnd syscall.Handle, msg uint32, wParam, lParam uintptr) uintptr
 			windows.SetCursor(w.cursor)
 			return windows.TRUE
 		}
+	case _WM_OPTION:
+		w.setOptions()
 	}
 
 	return windows.DefWindowProc(hwnd, msg, wParam, lParam)
@@ -520,6 +523,18 @@ func (w *window) readClipboard() error {
 }
 
 func (w *window) Option(opts *Options) {
+	w.mu.Lock()
+	w.opts = opts
+	w.mu.Unlock()
+	if err := windows.PostMessage(w.hwnd, _WM_OPTION, 0, 0); err != nil {
+		panic(err)
+	}
+}
+
+func (w *window) setOptions() {
+	w.mu.Lock()
+	opts := w.opts
+	w.mu.Unlock()
 	if o := opts.Size; o != nil {
 		dpi := windows.GetSystemDPI()
 		cfg := configForDPI(dpi)
diff --git a/app/internal/wm/os_x11.go b/app/internal/wm/os_x11.go
index b921d468..75b956e2 100644
--- a/app/internal/wm/os_x11.go
+++ b/app/internal/wm/os_x11.go
@@ -89,6 +89,7 @@ type x11Window struct {
 
 	mu        sync.Mutex
 	animating bool
+	opts      *Options
 
 	pointerBtns pointer.Buttons
 
@@ -98,6 +99,7 @@ type x11Window struct {
 		content []byte
 	}
 	cursor pointer.CursorName
+	mode   WindowMode
 }
 
 func (w *x11Window) SetAnimating(anim bool) {
@@ -124,22 +126,33 @@ func (w *x11Window) WriteClipboard(s string) {
 }
 
 func (w *x11Window) Option(opts *Options) {
-	dpy := w.x
-	win := w.xw
-	cfg := w.cfg
+	w.mu.Lock()
+	w.opts = opts
+	w.mu.Unlock()
+	w.wakeup()
+}
+
+func (w *x11Window) setOptions() {
+	w.mu.Lock()
+	opts := w.opts
+	w.opts = nil
+	w.mu.Unlock()
+	if opts == nil {
+		return
+	}
 	var shints C.XSizeHints
 	if o := opts.MinSize; o != nil {
-		shints.min_width = C.int(cfg.Px(o.Width))
-		shints.min_height = C.int(cfg.Px(o.Height))
+		shints.min_width = C.int(w.cfg.Px(o.Width))
+		shints.min_height = C.int(w.cfg.Px(o.Height))
 		shints.flags = C.PMinSize
 	}
 	if o := opts.MaxSize; o != nil {
-		shints.max_width = C.int(cfg.Px(o.Width))
-		shints.max_height = C.int(cfg.Px(o.Height))
+		shints.max_width = C.int(w.cfg.Px(o.Width))
+		shints.max_height = C.int(w.cfg.Px(o.Height))
 		shints.flags = shints.flags | C.PMaxSize
 	}
 	if shints.flags != 0 {
-		C.XSetWMNormalHints(dpy, win, &shints)
+		C.XSetWMNormalHints(w.x, w.xw, &shints)
 	}
 
 	var title string
@@ -148,9 +161,9 @@ func (w *x11Window) Option(opts *Options) {
 	}
 	ctitle := C.CString(title)
 	defer C.free(unsafe.Pointer(ctitle))
-	C.XStoreName(dpy, win, ctitle)
+	C.XStoreName(w.x, w.xw, ctitle)
 	// set _NET_WM_NAME as well for UTF-8 support in window title.
-	C.XSetTextProperty(dpy, win,
+	C.XSetTextProperty(w.x, w.xw,
 		&C.XTextProperty{
 			value:    (*C.uchar)(unsafe.Pointer(ctitle)),
 			encoding: w.atoms.utf8string,
@@ -190,6 +203,8 @@ func (w *x11Window) SetCursor(name pointer.CursorName) {
 
 func (w *x11Window) SetWindowMode(mode WindowMode) {
 	switch mode {
+	case w.mode:
+		return
 	case Windowed:
 		C.XDeleteProperty(w.x, w.xw, w.atoms.wmStateFullscreen)
 	case Fullscreen:
@@ -197,7 +212,34 @@ func (w *x11Window) SetWindowMode(mode WindowMode) {
 			32, C.PropModeReplace,
 			(*C.uchar)(unsafe.Pointer(&w.atoms.wmStateFullscreen)), 1,
 		)
+	default:
+		return
 	}
+	w.mode = mode
+	// "A Client wishing to change the state of a window MUST send
+	//  a _NET_WM_STATE client message to the root window (see below)."
+	var xev C.XEvent
+	ev := (*C.XClientMessageEvent)(unsafe.Pointer(&xev))
+	*ev = C.XClientMessageEvent{
+		_type:        C.ClientMessage,
+		display:      w.x,
+		window:       w.xw,
+		message_type: w.atoms.wmState,
+		format:       32,
+	}
+	arr := (*[5]C.long)(unsafe.Pointer(&ev.data))
+	arr[0] = 2 // _NET_WM_STATE_TOGGLE
+	arr[1] = C.long(w.atoms.wmStateFullscreen)
+	arr[2] = 0
+	arr[3] = 1 // application
+	arr[4] = 0
+	C.XSendEvent(
+		w.x,
+		C.XDefaultRootWindow(w.x), // MUST be the root window
+		C.False,
+		C.SubstructureNotifyMask|C.SubstructureRedirectMask,
+		&xev,
+	)
 }
 
 func (w *x11Window) ShowTextInput(show bool) {}
@@ -287,6 +329,7 @@ loop:
 				}
 			}
 		}
+		w.setOptions()
 		// Clear notifications.
 		for {
 			_, err := syscall.Read(w.notify.read, buf)
diff --git a/app/window.go b/app/window.go
index e8f691a9..20ee8b07 100644
--- a/app/window.go
+++ b/app/window.go
@@ -211,6 +211,17 @@ func (w *Window) Invalidate() {
 	}
 }
 
+// Option applies the options to the window.
+func (w *Window) Option(opts ...Option) {
+	go w.driverDo(func() {
+		o := new(wm.Options)
+		for _, opt := range opts {
+			opt(o)
+		}
+		w.driver.Option(o)
+	})
+}
+
 // ReadClipboard initiates a read of the clipboard in the form
 // of a clipboard.Event. Multiple reads may be coalesced
 // to a single event.