useDeferredValue lets you defer updating a part of the UI.
It stores a value of any type that will return the old value on the first re-render, and the new value on a re-render.
An example of use is for search queries. The results of searching for a can be deferred so it can continue to be displayed while the user modifies their search to ab.
Optionally an initialValue can be passed to be used during the initial render of the component.
It's made to be used with something [[reactsuspense]].