diff --git a/src/effects/diminactive/diminactive.cpp b/src/effects/diminactive/diminactive.cpp
index 88d27324d0..f89b4fa44b 100644
--- a/src/effects/diminactive/diminactive.cpp
+++ b/src/effects/diminactive/diminactive.cpp
@@ -369,6 +369,9 @@ void DimInactiveEffect::windowDeleted(EffectWindow *w)
     // gets destroyed immediately. So, we have to remove active transitions
     // for that window here, otherwise we'll crash in postPaintScreen.
     m_transitions.remove(w);
+    if (m_activeWindow == w) {
+        m_activeWindow = nullptr;
+    }
 }
 
 void DimInactiveEffect::activeFullScreenEffectChanged()