next: console errors

[jorgeorpinel]

For now only detected this one at /

Warning: Failed prop type: The prop `buttonText` is marked as required in `TrySection`, but its value is `undefined`.
    in TrySection
    in Unknown
    in Context.Provider
    in StyleSheetManager
    in Unknown
    in App
    in Context.Provider
    in Context.Provider
    in Context.Provider
    in Context.Provider
    in AppContainer

but we should probably check all pages including dynamic ones (inside /doc) for more, and address them.

There's also some warnings about cross-site cookies in Chrome and FF.