Include Quarto Markdown in LaTeX Raw Blocks

Use the syntax \QuartoMarkdownBase64{<<base64-encoded-markdown-content>>} to include Quarto Markdown in LaTeX raw blocks. When this syntax is detected by Quarto, the contents will be decoded, processed in Quarto (including user filters), and then inserted back into the LaTeX raw block. This allows libraries that emit raw blocks to benefit from Quarto features such as cross-reference resolution and shortcodes.

This is useful for third-party libraries that seek to emit LaTeX content that nevertheless can have “quarto content”. Note that, unlike the equivalent HTML feature, Quarto currently only supports base-64 encoded content in LaTeX blocks.

This LaTeX feature cannot currently be disabled. We expect this to not be necessary because QuartoMarkdownBase64 is unlikely to conflict with existing LaTeX environments.