diff --git a/glutin/src/application.rs b/glutin/src/application.rs
index b8e80ddf..0f748ecb 100644
--- a/glutin/src/application.rs
+++ b/glutin/src/application.rs
@@ -300,6 +300,9 @@ async fn run_instance<A, E, C>(
             _ => {}
         }
     }
+
+    // Manually drop the user interface
+    drop(ManuallyDrop::into_inner(user_interface));
 }
 
 fn build_user_interface<'a, A: Application>(
diff --git a/winit/src/application.rs b/winit/src/application.rs
index 07108249..3a41a0e4 100644
--- a/winit/src/application.rs
+++ b/winit/src/application.rs
@@ -383,6 +383,9 @@ async fn run_instance<A, E, C>(
             _ => {}
         }
     }
+
+    // Manually drop the user interface
+    drop(ManuallyDrop::into_inner(user_interface));
 }
 
 /// Returns true if the provided event should cause the [`Application`] to