Dendron[1] note taking extension for VS Code has Mermaid support builtin to its markdown renderer as well.

That's how I recently found that Mermaid can't handle graphs with no flow https://github.com/mermaid-js/mermaid/issues/1227

[1] https://wiki.dendron.so/notes/ba97866b-889f-4ac6-86e7-bb2d97...