dom-id returns "" for elements without an id attribute, and "" is
truthy in SX. This caused morph-children to build spurious entries
in old-by-id keyed by "", then match unrelated children via the
empty key — advancing oi past id-keyed children like #main-content
and skipping them in cleanup.
Three changes in morph-children (engine.sx):
- old-by-id reduce: normalize empty dom-id to nil so id-less
elements are excluded from the lookup dict
- match-id binding: normalize empty dom-id to nil so new children
without ids don't spuriously match old children
- Case 2 skip condition: use (not (empty? ...)) instead of bare
(dom-id old-child) to avoid treating "" as a real id
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>