react-markdown is a npm package that seeks to convert markdown into valid HTML without resorting to dangerouslySetHTML. There are some aspects of markdown syntax that it cannot handle, one of which is tables. react-markdown has a plugin ecosystem that helps out here and remark-gfm is a plugin that does handle markdown tables.

That package received an update to version 4.0.0 within the past few days and it now appears that markdown table rendering is broken. Including a table in your markdown leads to:

TypeError: Cannot read properties of undefined (reading 'inTable')

Reverting to remark-gfm version 3.0.1 resolves the issue.

npm uninstall remark-gfm

npm install remark-gfm@3.0.1