A userscript that collapses markdown headers

• This script makes all markdown headers clickable and toggles the view of all content between same level headers (e.g. between H2 headers).
• It works on readme, issues, markdown preview, wiki & gist pages. Pretty much everywhere on GitHub.
• Click on any header to toggle the view of the content below it.
• Use Shift + Click to toggle the view of all same level header content.
• When the content of a header is expanded, all sub-headers are also expanded.
• Links within the header are still clickable.
• Can be used along with the GitHub-table-of-contents & the GitHub-collapse-in-comment userscripts.
• Use the userscript addon to change these settings (see screenshot below):

  • "Set collapse markdown state" to collapsed (expanded by default) which collapses all header content initially.

  • "Set collapse markdown colors" to an JSON array with six color values (accepts named, hex, rgb, hsl, etc). For example:

    // palette generated by http://tools.medialab.sciences-po.fr/iwanthue/
    // (colorblind friendly; soft)
    ["#6778d0", "#ac9c3d", "#b94a73", "#56ae6c", "#9750a1", "#ba543d"]

  These six colors apply to the H1 through H6 header arrows respectively.
  • After changing either option, make sure to reload the page (Shift + F5) to have the updated setting take effect.
• Click this link to install from GitHub; or, install from GreasyFork or OpenUserJS.
• Or, you can install it as a browser addon. Check out Octopatcher!

Screenshot

Example

• Use with userscript installed
• Note: Shift + clicking on an H2 header below will also collapse this example block.

Header 1

• Inside header 1

Header 2

• Inside header 2
• Inside header 2

Header 3

• Inside header 3

Header 3

• Inside header 3

Header 4

• Inside header 4

Header 5

• Inside header 5
• Inside header 5

Header 5

• Inside header 5

Header 6

• Inside header 6

Header 4

• Inside header 4
• Inside header 4

Header 3

• Inside header 3

Header 3

• Inside header 3

Header 2

• Inside header 2

Header 3

Header 4

• Inside header 4
• Inside header 4

Change Log

Version 1.2.2 (2021-07-21)

• Update mutation script.

Version 1.2.1 (2021-01-31)

• Update mutation script.

Version 1.2.0 (2019-03-29)

• Ignore empty headers. Closes issue #79.

Version 1.1.13 (2019-02-16)

• Update GitHub icon.

Version 1.1.12 (2018-01-18)

• Update assets.

Version 1.1.11 (2017-10-03)

• Fix undefined variable.

Version 1.1.10 (2017-10-01)

• Code cleanup. Update to match Octopatcher code.

Version 1.1.9 (2017-05-24)

• Fix javascript error.

Version 1.1.8 (2017-05-16)

• Change license to MIT.

Version 1.1.7 (2017-03-25)

• Fix linting.

Version 1.1.6 (2017-01-11)

• Clean up "closest" function.
• Use classList toggle.

Version 1.1.5 (2016-12-18)

• Make user set options case-insensitive

Version 1.1.3 & 1.1.4 (2016-10-03)

• Show current state when changing option.
• Make code work on Firefox. Fixes issue #13.

Version 1.1.2 (2016-10-02)

• Change collapse markdown state choices to "collapsed" or "expanded".

Version 1.1.1 (2016-09-12)

• Beautify.

Version 1.1.0 (2016-07-30)

• Add support for GitHub-FixedHeader style.
• Include GitHub help pages.
• Fix lint & a code tweak.

Version 1.0.1 (2016-07-05)

• Don't toggle on link & image clicks.

Version 1.0.0 (2016-06-27)

• Initial commit.