Invisible links in mermaid

[cscheid]

Discussed in #3349

^{Originally posted by aghaynes November 16, 2022}
According to the help files for mermaid, it is possible to have invisible links between nodes in mermaid charts, which can be particularly useful for enforcing a particular layout. https://mermaid-js.github.io/mermaid/#/flowchart?id=an-invisisble-link E.g. the following code should produce the flowchart further down.

```{mermaid}
flowchart LR
  box1 --> box2
  box2 --- box3
  box4 ~~~ box2
```

Executing the chunk in quarto produces a syntax error though.

It seems like the invisible links are probably a new feature (there's an issue referencing a commit in mid-October - mermaid-js/mermaid#3192).

I guess this would require an update to the version of mermaid in quarto?

[fkohrt]

@cscheid It seems invisible links have been removed as a feature in mermaid v9.3.0 again. At least I cannot find the changes that were introduced by the following two commits neither in v9.3.0 nor in develop:

• mermaid-js/mermaid@eec97d1
• mermaid-js/mermaid@4d46ea9

[cscheid]

@fkohrt I apologize, but we will be upgrading mermaid once per release and no further; it's not sustainable for us to continually chase their changes. If your setup requires mermaid to be on the very latest version, I think the best shot is for you to download the github repo for quarto, and update mermaid.js and mermaid.min.js yourself based on the commit 75fd336.

[fkohrt]

@cscheid Thank you very much for your hints and pointers. However, there is no feature that a more recent version of mermaid has that I want. Rather, I wanted to inform you that in case you decide to bump your mermaid dependency in the future, you will have to re-open this issue, as invisible links have been removed as a feature in mermaid v9.3.0 (in contrast to your currently bundled v9.2.2). This is not actionable, just a heads-up :)

[cscheid]

@fkohrt I appreciate the heads up!

[fkohrt]

Invisible links will be re-introduced with mermaid v10.0.0 (see mermaid-js/mermaid#4113).