From 65a3701be379c6b7c08bc8956f94741eb6c73b17 Mon Sep 17 00:00:00 2001
From: Greg Kennedy <kennedy.greg@gmail.com>
Date: Tue, 29 Dec 2015 16:17:24 -0600
Subject: [PATCH] Switch to Fullscreen fails unless done after MapWindow.

---
 unix/x11.cpp | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/unix/x11.cpp b/unix/x11.cpp
index b16b6427..fe0dd9da 100644
--- a/unix/x11.cpp
+++ b/unix/x11.cpp
@@ -842,12 +842,6 @@ void S9xInitDisplay (int argc, char **argv)
 							WidthOfScreen(GUI.screen), HeightOfScreen(GUI.screen), 0,
 							GUI.depth, InputOutput, GUI.visual, CWBackPixel | CWColormap, &attrib);
 
-		/* Try to tell the Window Manager not to decorate this window. */
-		Atom wm_state   = XInternAtom (GUI.display, "_NET_WM_STATE", true );
-		Atom wm_fullscreen = XInternAtom (GUI.display, "_NET_WM_STATE_FULLSCREEN", true );
-
-		XChangeProperty(GUI.display, GUI.window, wm_state, XA_ATOM, 32, PropModeReplace, (unsigned char *)&wm_fullscreen, 1);
-
 #ifdef USE_XVIDEO
 		if (GUI.use_xvideo)
 		{
@@ -938,6 +932,21 @@ void S9xInitDisplay (int argc, char **argv)
 	XMapRaised(GUI.display, GUI.window);
 	XClearWindow(GUI.display, GUI.window);
 
+	// Wait for map
+	XEvent event;
+	do {
+		XNextEvent(GUI.display, &event);
+	} while (event.type != MapNotify || event.xmap.event != GUI.window);
+
+	if (GUI.fullscreen)
+	{
+		/* Try to tell the Window Manager not to decorate this window. */
+		Atom wm_state   = XInternAtom (GUI.display, "_NET_WM_STATE", true );
+		Atom wm_fullscreen = XInternAtom (GUI.display, "_NET_WM_STATE_FULLSCREEN", true );
+
+		XChangeProperty(GUI.display, GUI.window, wm_state, XA_ATOM, 32, PropModeReplace, (unsigned char *)&wm_fullscreen, 1);
+	}
+
 #ifdef USE_XVIDEO
 	if (GUI.use_xvideo)
 	{