# Objective
Avert a panic when removing resources from Scenes.
### Reproduction Steps
```rust
let mut scene = Scene::new(World::default());
scene.world.init_resource::<Time>();
scene.world.remove_resource::<Time>();
scene.clone_with(&app.resource::<AppTypeRegistry>());
```
### Panic Message
```
thread 'Compute Task Pool (10)' panicked at 'Requested resource bevy_time::time::Time does not exist in the `World`.
Did you forget to add it using `app.insert_resource` / `app.init_resource`?
Resources are also implicitly added via `app.add_event`,
and can be added by plugins.', .../bevy/crates/bevy_ecs/src/reflect/resource.rs:203:52
```
## Solution
Check that the resource actually still exists before copying.
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## Changelog
- resolved a panic caused by removing resources from scenes
0f20cfaa57