diff --git a/app/src/main/java/com/hawhamburg/micr0bu/ui/screens/V2xLiveMapView.kt b/app/src/main/java/com/hawhamburg/micr0bu/ui/screens/V2xLiveMapView.kt
index 91e3630..305d34f 100644
--- a/app/src/main/java/com/hawhamburg/micr0bu/ui/screens/V2xLiveMapView.kt
+++ b/app/src/main/java/com/hawhamburg/micr0bu/ui/screens/V2xLiveMapView.kt
@@ -85,7 +85,7 @@ fun V2xLiveMapView(
         lifecycleOwner.lifecycle.addObserver(observer)
         onDispose {
             lifecycleOwner.lifecycle.removeObserver(observer)
-            mapViewRef.value?.onDetach()
+            // onDetach() deliberately NOT called here - see AndroidView's onRelease below.
         }
     }
 
@@ -173,6 +173,20 @@ fun V2xLiveMapView(
                 mv.controller.animateTo(ownGeoPoint)
                 mv.invalidate()
             },
+            // osmdroid's onDetach() permanently tears the MapView down: afterwards its
+            // MapViewRepository holds a null MapView, so constructing a Marker against it throws
+            // NullPointerException from deep inside InfoWindow's constructor.
+            //
+            // This used to run in the DisposableEffect's onDispose, which is NOT safe: that effect
+            // is keyed on the lifecycle owner and disposes independently of this AndroidView, so
+            // the update block above could still run against an already-detached MapView and
+            // rebuild its markers. It crashed the app on 2026-08-17 once DENMs started arriving,
+            // because every incoming message recomposes this view and there are far more updates
+            // to land in that window than there used to be.
+            //
+            // onRelease is the callback that actually means "this View is gone": Compose
+            // guarantees no further update after it.
+            onRelease = { it.onDetach() },
             modifier = Modifier.fillMaxSize(),
         )
     }