# Objective
Ensure that components that are conditionally extracted do not linger in
the render world when not extracted from the main world.
## Solution
If the `ExtractComponent` returns `None`, we'll remove the render world
component. I think this is the most sensible behavior here. In the
future if there really is a use case for keeping the previous render
component around, we could add a `Option<Self::Out>` parameter for the
previous render component to the method, or something similar. I think
that this follows the principle of least surprise here relative to what
`None` would suggest and the way that render nodes are typically
written. The alternative would be to add an `enabled` field to pretty
much every camera settings component, or duplicate the extraction
condition as #15856 does.
## Testing
`transmission` no longer crashes.
## Migration Guide
Components that implement `ExtractComponent` and return `None` will
cause the extracted component to be removed from the render world.
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