I am glad that you managed to figure out the CascadingValue component's behavior since it is really useful to apply in such scenarios.
Indeed, if you want its specified value to be accessible from other components, they should be rendered inside the CascadingValue component.
As for the multiple @Body fragments you were experiencing, this is due to the @Body fragment being declared two times - once in the CascadingValue component and once more in the Drawer component. Only one instance of the @Body fragment has to be implemented as per your second example.
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