Do undocumented error number pages simply not exist?

A user [posted an error message containing an error code](https://discourse.haskell.org/t/cabal-quickstart-with-hls-pains/6867). It just so happens that it's `GHC-32850` (although the specific code doesn't matter for this issue). Google returns exactly one result for `"GHC-32850"` which is [a GHC GitLab issue containing a similar error message](https://gitlab.haskell.org/ghc/ghc/-/issues/23355).

I was surprised. I expected there to be a page for the error code in question, even if it says "this error message is not yet documented". In fact, that seems like an essential workflow for inexperienced users. Googling the code and getting no useful hits means that they haven't been helped by the index at all. On the other hand, if Google returns a link to a stub page that says "This error code is undocumented: please click here to file a GitHub issue to request documentation" that's really helpful!

So,

1. is it really the case that there are error codes that don't have pages, or have I missed something?
2. if so, what can I do to make sure they all get pages, even if they're just stubs?