Windows desktop app local Markdown preview shows LaTeX math as raw text

What version of the Codex App are you using?

26.901.4073.0 (Microsoft Store package OpenAI.Codex)

What platform are you using?

Windows desktop app. The package path identifies the x64 Windows build; the exact Windows OS build was not recorded.

What issue are you seeing?

The right-side preview for a local Markdown file renders headings, bold text, and lists, but does not render LaTeX math. Both the math delimiters and the LaTeX source are displayed literally. The same file renders its formulas correctly in the built-in Markdown preview in Windows VS Code.

Minimal reproduction

Save a local file named test.md with exactly:

# Math preview test

Inline: $x^2 + y^2 = z^2$

$$
\frac{1}{2} + \sqrt{x}
$$

Then:

1. Open test.md in the Codex Windows desktop app.
2. Switch the file tab to View preview.
3. Observe that $x^2 + y^2 = z^2$, $$, \frac, and \sqrt appear as raw text instead of formatted math.

Expected behavior

The local Markdown preview should render supported inline and display math, including $...$ and $$...$$, or clearly document which math delimiters are unsupported.

Actual behavior

The rest of the Markdown preview is formatted, but the math delimiters and LaTeX commands remain literal source text.

Additional context

This report is about the Windows desktop app's local file preview path. It is separate from terminal/TUI math rendering and from the VS Code extension preview. No screenshot or local project file is attached.

As a local read-only implementation note, the desktop file preview bundle appears to use a CodeMirror Markdown parser and decorations for headings, lists, tables, links, images, and code. I did not find a math node or a KaTeX integration on this file-preview path, although other app bundles contain KaTeX code. This may explain why ordinary Markdown renders while math remains source text.

Start with the desktop file-preview bundle, focusing on its CodeMirror Markdown parser and decorations for headings, lists, tables, links, images, and code. Compare this path with the other app bundles containing KaTeX code; done means the supplied test.md renders inline and display math, or the supported delimiters are clearly documented.