sup element rendering with remark-gfm plugin is painfully slow.

[tgram-3D]

Initial checklist

• I read the support docs
• I read the contributing guide
• I agree to follow the code of conduct
• I searched issues and couldn’t find anything (or linked relevant results below)

Affected packages and versions

react-markdown 9.0.1, remark-gfm 4.0.0

Link to runnable example

No response

Steps to reproduce

I'm using ReactMarkdown to render streaming LLM tokens, which seems to be a common use-case, and I'm trying to get it to render footnotes correctly. It works, but basically the entire paragraph renders fine in markdown but the [^1], [^2] formatted footnotes just sit there basically and don't get rendered as sup until the entire p element is complete.

<ReactMarkdown
                        remarkPlugins={[remarkGfm, remarkMath]}
                        rehypePlugins={[
                            rehypeKatex,
                            [
                                //@ts-expect-error version 6.0.0
                                rehypeHighlight,
                                {
                                    detect: true,
                                    ignoreMissing: true,
                                    subset: codeLanguageSubset
                                }
                            ]
                        ]}
                        components={components}
                    >
                        {content}
                    </ReactMarkdown>

I tried a custom component for sup and same deal. Is there a better way to do this sort of thing? I'm thinking I just get rid of remarkGfm and target superscript formatting in my custom p component directly, but it seems like there should be a better solution.

One thing that's kind of interesting is the back-ref a tags in the footnotes section render just fine, but not the actual sup elements.

Using node 20.12.0 and npm 10.5.0

Expected behavior

Footnotes rendered on streaming.

Actual behavior

Footnote rendering lags significantly and doesn't work until entire paragraph element is rendered.

Runtime

Other (please specify in steps to reproduce)

Package manager

Other (please specify in steps to reproduce)

OS

Windows

Build and bundle tools

Vite

[wooorm]

It is unclear what you see because you have not shared what you see.

[remcohaszing]

Markdown can’t be streamed. Footnotes and definitions can appear at the end of a document, meaning the entire markdown document needs to be parsed in order to know whether or not something that looks like a footnote reference of link reference is actually a reference or just plain text.

This doesn’t stop people from streaming markdown anyway.

---

This paragraph has only one footnote[^1][^2].

[^1]: Footnote

This paragraph has only one footnote¹[^2].

Footnotes

1. Footnote ↩

[wooorm]

This is what I am assuming too.

Nothing is “painful” here. You’re just streaming things and observe that things are streamed.

[tgram-3D]

Markdown can’t be streamed. Footnotes and definitions can appear at the end of a document, meaning the entire markdown document needs to be parsed in order to know whether or not something that looks like a footnote reference of link reference is actually a reference or just plain text.

This doesn’t stop people from streaming markdown anyway.

This paragraph has only one footnote[^1][^2].

[^1]: Footnote

This paragraph has only one footnote1[^2].

Footnotes

1. Footnote ↩

Ah, duh. That makes sense. I guess I don't understand how it's actually inferring the href for the a tags in the footnotes, cause I'm seeing the same behavior with totally fake content. I'll mark this as closed and figure something else out. Thanks for the replies.

[github-actions]

Hi! Thanks for reaching out! Because we treat issues as our backlog, we close issues that are questions since they don’t represent a task to be completed.

See our support docs for how and where to ask questions.

Thanks,
— bb