404 links go to a blank page

[dwsilk]

e.g. https://2019.foss4g-oceania.org/brokenlink/

Might be nice to add a little message and redirect back to home.

[alpha-beta-soup]

I had a go at implementing this, and the work is in a branch: https://github.com/foss4g-oceania/hoverboard/tree/404 (Direct link to diff.)

I got as far as reaching a 404.html document if navigated directly to it. However, still the same behaviour otherwise. I'm not familiar with Firebase hosting beyond this project so I'm not really sure what else to try. Perhaps there's something to tweak in the console?

Docs are here: https://firebase.google.com/docs/hosting/full-config#404

There's nothing in upstream Hoverboard fork about a 404 page that I can see, just a few opaque issues; but it might be worth raising a new issue there to at least ask how. It would be better to rebase our fork first.

The existing config, if I'm interpreting it correctly, should already redirect back to index.html (albeit silently). That it doesn't, AFAICT, is a bug. The client doesn't actually seem to get either a 4XX or 3XX response at any point.