`renderPage` equivalent for page level components

[attapurposevc]

Hi,
Currently, we can pass the through the renderPage through the _document.js for decorating our components. This seems a bit restrictive, since I want to decorate one of my pages on the server side.

I've looked into it, there seems no straightforward way of accomplishing this. Correct me if I'm wrong. If there isn't, then I'll start making a pull request.

• I have searched the issues of this repository and believe that this is not a duplicate.

[tz5514]

I think you can check this out #3552.

[timneutkens]

There's a few PRs and other issues about this. closing this one.