Server rendering frameworks such as next can only request server-side data on page pages, and components can only request data through http, so data is often transferred to the component one layer down through props on page pages.
Generally, this kind of problem will be solved by context in react. Next.js, as a react ssr framework, can also use context. In a custom App, you can intercept the data requested by the page (or directly take _ _ NEXT_DATA__), and then set the data to context, usually initialReduxState, and then directly useSelector the ssr data in the component.
Next redux rule: all the data on the page is placed in initialReduxState, the data of ssr is set to a specific value, and the data of csr is set to null when ssr