Hello,

I am using a shared metadata yaml for all my documents, which contains definitions, which I need in all of my documents, for example:

---
documentclass: article
header-includes:
  - \usepackage{tikz}

---

Now, I have some document, in which I want to overwrite/extend some values:

---
documentclass: IEEEtran
header-includes:
  - \IEEEspecialpapernotice{Some notice}

---

I would have expected, that the documentclass (since it is a single-value type) gets overridden and the header-includes (since it is an array) gets extended.
Instead, the values specified in my document got completely ignored.

I compiled the document with the following options:

pandoc --standalone --filter pandoc-citeproc -f markdown+yaml_metadata_block+example_lists+implicit_figures+citations -o ./subject/document.pdf ./pandoc/meta.yaml  ./subject/document.md

Is there a way to achieve my expected behaviour?