diff --git a/xkeymap.c b/xkeymap.c
index 2794497..a9f8085 100644
--- a/xkeymap.c
+++ b/xkeymap.c
@@ -44,6 +44,8 @@ extern int g_keyboard_subtype;
 extern int g_keyboard_functionkeys;
 extern int g_win_button_size;
 extern RD_BOOL g_enable_compose;
+extern RD_BOOL g_seamless_rdp;
+extern RD_BOOL g_seamless_active;
 extern RDP_VERSION g_rdp_version;
 extern RD_BOOL g_numlock_sync;
 
@@ -644,7 +646,21 @@ handle_special_keys(uint32 keysym, unsigned int state, uint32 ev_time, RD_BOOL p
 			{
 				/* Ctrl-Alt-Enter: toggle full screen */
 				if (pressed)
-					xwin_toggle_fullscreen();
+				{
+					if (!g_seamless_rdp)
+					{
+						/* only allow toggle fullscreen when not running
+						   rdesktop in seamless mode */
+						xwin_toggle_fullscreen();
+					}
+					else
+					{
+						/* deactivate seamless mode for debug purpose, one can
+						   not activate seamless mode again  */
+						if (g_seamless_active)
+							ui_seamless_toggle();
+					}
+				}
 				return True;
 			}
 			break;
diff --git a/xwin.c b/xwin.c
index 1df1a8a..cb64064 100644
--- a/xwin.c
+++ b/xwin.c
@@ -101,7 +101,7 @@ typedef struct _seamless_window
 static seamless_window *g_seamless_windows = NULL;
 static unsigned long g_seamless_focused = 0;
 static RD_BOOL g_seamless_started = False;	/* Server end is up and running */
-static RD_BOOL g_seamless_active = False;	/* We are currently in seamless mode */
+RD_BOOL g_seamless_active = False;	/* We are currently in seamless mode */
 static RD_BOOL g_seamless_hidden = False;	/* Desktop is hidden on server */
 static RD_BOOL g_seamless_broken_restack = False;	/* WM does not properly restack */
 extern RD_BOOL g_seamless_rdp;
@@ -2257,9 +2257,9 @@ xwin_toggle_fullscreen(void)
 {
 	Pixmap contents = 0;
 
-	if (g_seamless_active)
-		/* Turn off SeamlessRDP mode */
-		ui_seamless_toggle();
+	/* When running rdesktop in seamless mode, toggling of fullscreen is not allowed */
+	if (g_seamless_rdp)
+		return;
 
 	if (!g_ownbackstore)
 	{