diff --git a/source/clog-gui.lisp b/source/clog-gui.lisp
index dd6eef9..91903a4 100644
--- a/source/clog-gui.lisp
+++ b/source/clog-gui.lisp
@@ -386,7 +386,6 @@ in on-resize, on-full-screen-change and on-orientation-change events."))
     (maphash (lambda (key value)
                (declare (ignore key))
                (cond ((window-maximized-p value)
-                      (window-normalize value :focus nil)
                       (window-maximize value :focus nil))
 		     (t
 		      (make-in-bounds value mbh bh bw))))
@@ -784,6 +783,14 @@ The on-window-change clog-obj received is the new window"))
     (set-on-pointer-move obj nil)
     (set-on-pointer-cancel obj nil)
     (set-on-pointer-up obj nil)
+    (cond ((window-maximized-p (drag-obj app))
+           (window-maximize (drag-obj app) :focus nil))
+	  (t
+	   (let* ((body      (connection-data-item (drag-obj app) "clog-body"))
+		  (mbh       (menu-bar-height (drag-obj app)))
+		  (bh        (height (html-document body)))
+		  (bw        (width  (html-document body))))
+	     (make-in-bounds (drag-obj app) mbh bh bw))))
     (cond ((equalp (in-drag app) "m")
            (fire-on-window-move-done (drag-obj app)))
           ((equalp (in-drag app) "s")
@@ -1053,26 +1060,27 @@ the browser."))
 :focus (default t)."))
 
 (defmethod window-maximize ((obj clog-gui-window) &key (focus t))
-  (let ((app (connection-data-item obj "clog-gui")))
-    (when focus
-      (unless (keep-on-top obj)
-	(window-focus obj)))
-    (when (fire-on-window-can-maximize obj)
-      (unless (window-maximized-p obj)
-        (setf (last-x obj) (left obj))
-        (setf (last-y obj) (top obj))
-        (setf (last-height obj) (height obj))
-        (setf (last-width obj) (width obj)))
-      (setf (top obj) (unit :px (menu-bar-height obj)))
-      (setf (left obj) (unit :px 0))
-      (setf (width obj) (unit :vw 100))
-      (setf (left obj) (unit :px (body-left-offset app)))
-      (setf (width obj) (- (width obj)
-                           (body-left-offset app)
-                           (body-right-offset app)))
-      (setf (height obj)
-            (- (inner-height (window (body app))) (menu-bar-height obj)))
-      (fire-on-window-size-done obj))))
+  (with-sync-event (obj) ; prevent race condition of maximize/normalize
+    (let ((app (connection-data-item obj "clog-gui")))
+      (when focus
+	(unless (keep-on-top obj)
+	  (window-focus obj)))
+      (when (fire-on-window-can-maximize obj)
+	(unless (window-maximized-p obj)
+          (setf (last-x obj) (left obj))
+          (setf (last-y obj) (top obj))
+          (setf (last-height obj) (height obj))
+          (setf (last-width obj) (width obj)))
+	(setf (top obj) (unit :px (menu-bar-height obj)))
+	(setf (left obj) (unit :px 0))
+	(setf (width obj) (unit :vw 100))
+	(setf (left obj) (unit :px (body-left-offset app)))
+	(setf (width obj) (- (width obj)
+                             (body-left-offset app)
+                             (body-right-offset app)))
+	(setf (height obj)
+              (- (inner-height (window (body app))) (menu-bar-height obj)))
+	(fire-on-window-size-done obj)))))
 
 ;;;;;;;;;;;;;;;;;;;;;;
 ;; window-normalize ;;
@@ -1083,17 +1091,18 @@ the browser."))
 :focus (default t)."))
 
 (defmethod window-normalize ((obj clog-gui-window) &key (focus t))
-  (when focus
-    (unless (keep-on-top obj)
-      (window-focus obj)))
-  (when (fire-on-window-can-normalize obj)
-    (when (window-maximized-p obj)
-      (setf (width obj) (last-width obj))
-      (setf (height obj) (last-height obj))
-      (setf (top obj) (last-y obj))
-      (setf (left obj) (last-x obj))
-      (setf (last-width obj) nil)
-      (fire-on-window-size-done obj))))
+  (with-sync-event (obj) ; prevent race condition of maximize/normalize
+    (when focus
+      (unless (keep-on-top obj)
+	(window-focus obj)))
+    (when (fire-on-window-can-normalize obj)
+      (when (window-maximized-p obj)
+	(setf (width obj) (last-width obj))
+	(setf (height obj) (last-height obj))
+	(setf (top obj) (last-y obj))
+	(setf (left obj) (last-x obj))
+	(setf (last-width obj) nil)
+	(fire-on-window-size-done obj)))))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; window-toggle-maximize ;;
@@ -1399,15 +1408,6 @@ interactions. Use window-end-modal to undo."))
   (setf (on-window-move-done obj) handler))
 
 (defmethod fire-on-window-move-done ((obj clog-gui-window))
-  (cond ((window-maximized-p obj)
-         (window-normalize obj :focus nil)
-         (window-maximize obj :focus nil))
-	(t
-	 (let* ((body      (connection-data-item obj "clog-body"))
-		(mbh       (menu-bar-height obj))
-		(bh        (height (html-document body)))
-		(bw        (width  (html-document body))))
-	   (make-in-bounds obj mbh bh bw))))
   (when (on-window-move-done obj)
     (funcall (on-window-move-done obj) obj)))