A tab left open across a release asked for a lazy chunk the server no
longer has (prod: DownloadDialog 404 an hour after 0.89) and fell to the
crash screen. `vite:preloadError` now reloads the tab once a minute at
most; a second failure is let through to the error boundary, which now
wraps every entry — the public /watch, /privacy and /terms pages crashed
to a blank page.