A post created with the editor stored sx_content containing components the host
can't resolve: the legacy editor emits bare ~kg-md while the cards are
~kg_cards/kg-md (drift — not papered over with aliases). render-to-html threw on
the undefined symbol and host/blog-render had no error handling -> handler crash
-> 502 on a REAL post (/mddddd/).
Fix: render each block of the (<> ...) fragment under its own guard via
render-page (env-supplied). Real prose (p/h1/ul/...) renders; an unsupported or
malformed block degrades to a <div class=blk-unsupported> placeholder; a bad
block never crashes the handler. Verified live: /mddddd/ + all junk posts now
200 (text shown, cards placeheld). Full kg-card rendering = follow-on (resolve
the name drift / native editor).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
giles
3369166a03