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RehypeMermaid plugin not working

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
38/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
react, typescript
Domain
frontend, web-dev

Research direction

Reproduce the supplied TypeScript/React example with the Mermaid fenced block and inspect how rehypePlugins is passed to MarkdownPreview. Compare the output with the expected Mermaid diagram; done means the block is processed as a diagram rather than rendered as plain code.

Written by the indexing model from the issue text.

Description

This is the code I'm rendering with:-

import React from 'react';
import MarkdownPreview from '@uiw/react-markdown-preview';
import rehypeMermaid from 'rehype-mermaidjs';

export default function MyMarkdownPreview({ data, setData }: { data: string; setData: (data: string) => void }) {
	return (
		<MarkdownPreview
			source={data}
			wrapperElement={{
				'data-color-mode': 'light',
			}}
			rehypePlugins={[rehypeMermaid]}
			rehypeRewrite={(node, index, parent) => {
				// eslint-disable-next-line @typescript-eslint/ban-ts-comment
				// @ts-ignore
				if (node.tagName === 'a' && parent && /^h(1|2|3|4|5|6)/.test(parent.tagName as string)) {
					parent.children = parent.children.slice(1);
				}
			}}
		/>
	);
}

The md text I'm rendering with:-

```mermaid
  graph TD;
      A-->B;
      A-->C;
      B-->D;
      C-->D;
```

It just renders it like this:-
image

Dominant language
TypeScript
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Forks
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