diff --git a/src/windowManager.cpp b/src/windowManager.cpp
index 3d14f16..a0b9590 100644
--- a/src/windowManager.cpp
+++ b/src/windowManager.cpp
@@ -372,14 +372,14 @@ void CWindowManager::refreshDirtyWindows() {
                 
             setEffectiveSizePosUsingConfig(&window);
 
-            // Fullscreen flag
-            bool bHasFullscreenWindow = getWorkspaceByID(window.getWorkspaceID())->getHasFullscreenWindow();
-
             const auto PWORKSPACE = getWorkspaceByID(window.getWorkspaceID());
 
             if (!PWORKSPACE)
                 continue;
 
+            // Fullscreen flag
+            bool bHasFullscreenWindow = PWORKSPACE->getHasFullscreenWindow();
+
             // first and foremost, let's check if the window isn't on a hidden workspace
             // or an animated workspace
             if (!isWorkspaceVisible(window.getWorkspaceID())