Mermaid charts embedded in Markdown show "Unable to render rich display" when using a dark theme

[parasyte]

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Bug

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Here's an example mermaid flowchart:

flowchart LR
  N0 --> N1
  N0 --> N3
  N1 --> N2
  N3 --> N2

Loading

When using any of the dark themes, the renderer sits on a spinner for around 45 seconds, then shows:

I can only get Mermaid to render in markdown when I use any of the light mode themes:

---

Standalone mmd files render correctly. It only fails when embedded in markdown.

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[victormoni]

Mermaid charts in Markdown fail to render when using dark themes.
The renderer hangs for ~45 seconds and then shows "Unable to render rich display".

• ✅ Works in light themes.
• ✅ Standalone .mmd files render correctly.
• ❌ Fails only when embedded in Markdown with dark themes.