`\n` in node labels rendered literally instead of as a newline

[mikejhill]

Environment

• Extension: Markdown Preview Mermaid Support v1.32.0
• VS Code: 1.112.0

Description

\n sequences in node labels are rendered as text rather than line breaks.

It seems this is a regression introduced in Mermaid v11.0.0. It worked correctly in Mermaid 10.9.3. See mermaid-js/mermaid#6048.

Interestingly, mermaid.live renders \n correctly for the same diagram. It's not clear to me whether they're preprocessing the text or using different renderer logic.

Example

```mermaid
graph TB
    A["Line one\nLine two"]
    B["GCP Origin\n(single region)"]
```

Actual (Markdown Preview Extension)

Expected (GitHub)

graph TB
    A["Line one\nLine two"]
    B["GCP Origin\n(single region)"]

Loading

Workaround

Replacing \n with <br> works. I can actually only find <br> in the docs (link), but it seems many renderers support \n, including mermaid.live, GitHub's GFM, and (until its own regression) Mermaid.js itself.

---

I assume this could just be addressed by the upstream fix after it is available. However, given the original issue is 1.5 years old and only recently got a response, it may be helpful to have an interim fix to cover the gap, such as preprocessing \n in quoted labels to replace with <br>. This would resolve a lot of the confusion we're seeing with Markdown authored in other sources today, particularly as Markdown is becoming increasingly popular and important with the trend in documentation-centric approaches.

[CAVAh]

UP