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Filter Params Blob Too Large

pandoc
The QUARTO_FILTER_PARAMS payload passed to pandoc’s Lua filters exceeds the platform’s environment-block size limit.

Q-20-4 — Filter Params Blob Too Large

The QUARTO_FILTER_PARAMS payload passed to pandoc’s Lua filters exceeds the platform’s environment-block size limit.

What this means

Quarto passes configuration to pandoc’s Lua filters through a single environment variable, QUARTO_FILTER_PARAMS, carrying a base64-encoded JSON payload. Some platforms (Windows, via CreateProcess) reject an entire environment block larger than 32,767 characters. When the built payload would exceed that limit, the subprocess cannot even be started with the parameters it needs.

Why this happens

The most common cause is a large include-in-header (or similar) file whose full text gets inlined into the params payload rather than referenced by path.

How to fix

Reduce the size of whatever content is being inlined into filter params — most commonly, shrink or split a large include-in-header file. There is currently no automatic fallback to a temp-file-based transport for oversized payloads.