# @gerhobbelt/markdown-it-github-headings

> Add GitHub style anchor tags to headers

Latest version **2.0.0-2** (published 2021-03-05) · ISC license · 0 weekly downloads

## Install

```sh
npm install @gerhobbelt/markdown-it-github-headings
pnpm add @gerhobbelt/markdown-it-github-headings
yarn add @gerhobbelt/markdown-it-github-headings
bun add @gerhobbelt/markdown-it-github-headings
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 2.0.0-2 |
| Published | 2021-03-05 |
| First published | 2020-07-03 |
| Weekly downloads | 0 |
| License | ISC |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 2 |
| Unpacked size | 55.4 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 25 |
| Author | Dan Flettre |
| Maintainers | gerhobbelt |
| Keywords | anchor, github, headers, links, markdown, markdown-it-plugin |

## Links

- npm: https://www.npmjs.com/package/@gerhobbelt/markdown-it-github-headings
- Repository: https://github.com/Flet/markdown-it-github-headings
- Homepage: https://github.com/Flet/markdown-it-github-headings#readme
- Issues: https://github.com/Flet/markdown-it-github-headings/issues
- npm.io page: https://npm.io/package/@gerhobbelt/markdown-it-github-headings

## Dependencies (2)

- [innertext](https://npm.io/package/innertext.md) 1.0.3
- [github-slugger](https://npm.io/package/github-slugger.md) 1.3.0

## Alternatives

- [@mdxeditor/editor](https://npm.io/package/@mdxeditor/editor.md) — 962.4K weekly downloads
- [mmdb-lib](https://npm.io/package/mmdb-lib.md) — 680.9K weekly downloads
- [playcanvas](https://npm.io/package/playcanvas.md) — 36.2K weekly downloads
- [@glw907/cairn-cms](https://npm.io/package/@glw907/cairn-cms.md) — 967 weekly downloads
- [markdown-to-confluence](https://npm.io/package/markdown-to-confluence.md) — 103 weekly downloads

## Recent versions

- 2.0.0-2 (latest) — 2021-03-05
- 2.0.0-1 — 2020-07-03

## README

# markdown-it-github-headings

Add GitHub style anchor tags to headers

[![npm][npm-image]][npm-url]
[![travis][travis-image]][travis-url]

[npm-image]: https://img.shields.io/npm/v/markdown-it-github-headings.svg?style=flat-square
[npm-url]: https://www.npmjs.com/package/markdown-it-github-headings
[travis-image]: https://img.shields.io/travis/Flet/markdown-it-github-headings.svg?style=flat-square
[travis-url]: https://travis-ci.org/Flet/markdown-it-github-headings


## Install

```
npm install --save @gerhobbelt/markdown-it-github-headings
```

## Usage

```js
var md = require('@gerhobbelt/markdown-it')()
  .use(require('@gerhobbelt/markdown-it-github-headings'), options)

md.render('# hello')
```

## Options and Defaults

The defaults will make the heading anchors behave as close to how GitHub behaves as possible.

Name              | Description                                                    | Default
------------------|----------------------------------------------------------------|-----------------------------------
`className`                     | name of the class that will be added to the anchor tag               | `anchor`
`prefixHeadingIds`              | add a prefix to each heading ID. *(see security note below)*         | `true`
`prefix`                        | if `prefixHeadingIds` is true, use this string to prefix each ID.    | `user-content-`
`enableHeadingLinkIcons`        | Adds the icon <svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewbox="0 0 16 16" width="16"><path d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg> next to each heading | `true`
`linkIcon`                      | If `enableHeadingLinkIcons` is true, use this to supply a custom icon (or anything really) | <svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewbox="0 0 16 16" width="16"><path d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg>
`resetSlugger`                     | reset the slugger counter between .render calls for duplicate headers. (See tests for example)              | true


## Why should I prefix heading IDs?

When using user generated content, its possible to run into **DOM Clobbering** when heading IDs are generated. Since IDs are used by JavaScript and CSS, a user could craft a page that breaks functionality or styles. A good way to avoid clobbering is to add a prefix to every generated ID to ensure they cannot overlap with existing IDs.

If you have full control over the content, there is less of a risk, but be aware that strange bugs related to DOM Clobbering are still possible!

For more information, here are some good resources on the topic:
- [User-generated content and DOM clobbering](http://opensoul.org/2014/09/05/dom-clobbering/)
- [In the DOM, no one will hear you scream](https://www.slideshare.net/x00mario/in-the-dom-no-one-will-hear-you-scream)
- [A discussion about GitHub implementation](https://github.com/jch/html-pipeline/pull/111#issuecomment-34369984)
- [An open issue on markdown-it repo](https://github.com/markdown-it/markdown-it/issues/28)


### But the prefixes make links look real gross.

One solution is to write some client side JavaScript to force non-prefixed hashes to jump to prefixed anchors. This is how its handled on GitHub and npmjs.com.

Check out [marky-deep-links](https://github.com/Flet/marky-deep-links) for an example (works great with browserify or webpack).


## Contributing

Contributions welcome! Please read the [contributing guidelines](CONTRIBUTING.md) first.

## License

[ISC](LICENSE.md)

---
_Source: https://npm.io/package/@gerhobbelt/markdown-it-github-headings · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._