I had just learned about Mermaid and used it standalone once, when I realized it is also already built into Github Markdown [0], where you can include a diagram by just going ```mermaid <code>```, which is veeery handy. In mermaid.live can also get an SVG URL which works great to paste into many online drawing tools like Miro, Diagrams.net etc.
The interface is a bit clunky (when the diagram text is invalid, you see markup) but it makes it easy to create diagrams that are embeddable in Google docs without reaching for google draw.
I don't know about the others, but Azure DevOps' mermaid support is several releases out of date, or custom-limited to certain features. This means a lot of the examples in the official docs or elsewhere online don't work.
But what is most frustrating is that they don't document what features or version of mermaid they actually support. Microsoft gives a couple examples with links to official Mermaid docs, with a huge vague warning that _some_ things won't work in DevOps.
I think you can embed the mermaid text directly into draw.io/diagrams.net. It becomes a boxed object so a bit painful to edit but make it easy to get a quick diagram up.
[0] https://docs.github.com/en/get-started/writing-on-github/wor...