The right-rail file preview rendered markdown through Streamdown with no
plugins and no math preprocessing, so $...$ and \(...\) stayed as raw
source text. Wire the memoized KaTeX plugin (same one the chat transcript
uses) into the preview and preprocess prose with a math-only normalizer that
skips chat-only transforms (reasoning-block stripping, session-ref linking,
preview-target stripping, URL autolinking, citation stripping) so a file's
prose, code fences, and inline code spans are never mangled.
- preview-file.tsx: import + module-scope createMemoizedMathPlugin, pass
plugins={{ math }} to Streamdown, preprocess text with
normalizeFilePreviewMath before render
- markdown-preprocess.ts: add exported normalizeFilePreviewMath
- markdown-preprocess.file-preview.test.ts: 8 tests (currency escaping,
delimiter normalization, fence/inline-code preservation, verbatim
citations/URLs/reasoning blocks)
hermes-seaeye[bot]