In Obsidian v0.9.20 this already works so IMHO this request can be archived.
- triple backticks can be preceded ..
- .. only by indentation, not by hyphen.
- so put code block on next line under list item mark "- "
- and indent it more.
- hyphen has to be followed by spaceand indent it more
to act as list item.
-
```mermaid
graph LR
A --> B
```
- see visualization of whitespace characters
- e.g. in EmEditor