Fix crash on Qt6/KF6

src/eventhandler.cpp

@@ -231,9 +231,12 @@ bool EventHandler::isHidden()
         }
     }
 
-    if (m_event->isStateEvent() && eventCast<const StateEvent>(m_event)->repeatsState()) {
+    if (m_event->isStateEvent()) {
+        auto *stateEvent = eventCast<const StateEvent>(m_event);
+        if (stateEvent && stateEvent->repeatsState()) {
             return true;
         }
+    }
 
     // isReplacement?
     if (auto e = eventCast<const RoomMessageEvent>(m_event)) {