remark GFM does not parse URLs end with _ properly

[fourdim]

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

remark-gfm@4.0.0

Link to runnable example

https://stackblitz.com/edit/github-cbrfbi?file=src%2Fmain.ts

Steps to reproduce

Let remark GFM parse following markdown:

https://example.com/MuawcBMT1Mzvoar09-_66?mode=page&blockIds=rL2_GXbtLU2SsJVfCSmh_

Expected behavior

URL should be parsed to

<https://example.com/MuawcBMT1Mzvoar09-_66?mode=page&blockIds=rL2_GXbtLU2SsJVfCSmh_>

Actual behavior

URL is parsed to

<https://example.com/MuawcBMT1Mzvoar09-_66?mode=page&blockIds=rL2_GXbtLU2SsJVfCSmh>\_

Runtime

Node v16

Package manager

pnpm

OS

Linux

Build and bundle tools

Vite

[ChristianMurphy]

Welcome @fourdim! 👋

That is the expected behavior.
This library matches GitHub, GitHub doesn't include the underscore.
See your example as parsed on GitHub below.

https://example.com/MuawcBMT1Mzvoar09-_66?mode=page&blockIds=rL2_GXbtLU2SsJVfCSmh_