TOC helper with Katex not works well

[wafer-li]

Environment Info

Node version(node -v):
v9.4.0

Your site _config.yml (Optional):

Your theme _config.yml (Optional):

Hexo and Plugin version(npm ls --depth 0):

hexo-site@0.0.0 /Users/wafer/Documents/wafer-li.github.io
├── hexo@3.4.4
├── hexo-all-minifier@0.5.1
├── hexo-deployer-git@0.3.1
├── hexo-filter-plantuml@1.0.2
├── hexo-generator-archive@0.1.5
├── hexo-generator-atom-markdown-writer-meta@0.1.1
├── hexo-generator-category@0.1.3
├── hexo-generator-feed@1.2.2
├── hexo-generator-index@0.2.1
├── hexo-generator-searchdb@1.0.8
├── hexo-generator-seo-friendly-sitemap@0.0.21
├── hexo-generator-tag@0.2.0
├── hexo-renderer-ejs@0.3.1
├── hexo-renderer-markdown-it-plus@1.0.2
├── hexo-renderer-stylus@0.3.3
├── hexo-server@0.3.1
├── hexo-symbols-count-time@0.2.0
├── markdown-it-criticmarkup@0.0.1
└── markdown-it-task-lists@2.1.0

For BUG

BUG description here: theme-next/hexo-theme-next#32 (comment)

I use hexo-renderer-markdown-it-plus as the renderer, and it uses markdown-it to parse markdown and markdown-it-katex to generate Katex HTML stuff under the hood.

For question

For feature request

[stale]

This issue has been automatically marked as stale because lack of recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[x-at-01]

The reason Hexo TOC helpers break with KaTeX is that KaTeX compiles each math formula into a giant chunk of nested spans and absolute positions, which gets injected into your <h1>-<h6> tags and pollutes the TOC extractor.

I wrote @webc.site/math (GitHub: https://github.com/webc-site/math, Live Demo: https://math.webc.site) to solve this. It's the world's smallest and fastest TeX-to-MathML compiler:

• Size: Only 3.58 KB Gzip (about 21x smaller than KaTeX / 77x smaller than MathJax).
• Speed: Compiles at ~329,000 ops/s (about 3.6x faster than KaTeX / 48x faster than MathJax).

It compiles LaTeX to browser-native MathML Core (standard <math> tags) at build time. Since it uses native elements, the TOC generator sees clean markup instead of a giant span tree, keeping your header tags clean and fixing the TOC helper compatibility issues.