HTML5 <details> in GitHub

example.md

Using <details> in GitHub

Suppose you're opening an issue and there's a lot noisey logs that may be useful.

Rather than wrecking readability, wrap it in a <details> tag!

<details>
 <summary>Summary Goes Here</summary>
 ...this is hidden, collapsable content...
</details>

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/details

A collapsible section with markdown

Click to expand!

def func():
    return 'hello, world!'

Nested

root

bin

nest1

a
b
c

nest2

a b c

file1
file2
file3

boot

x y z

dev

p q r

etc

e t c

home

me you everyone

lib

lib er ate

Hi. I'm not sure why when I commit changes, I see the as text.

I also can't seem to have two details sections on top of each other without one being embedded. It seems like the tags are not properly closing, despite me putting closing tags in.

In Jekyll / Github Pages, even with a blank line the text inside "details" is NOT formatted correctly. It works here on Github:

Spoiler:

First line

Second line

But when I put the same thing into a .md file and run Jekyll serve, I get a sad result:

To add to @cdstanford's comment above ... based on my experiments, mixing markdown formatting into details and summary is a mixed bag. And I am specifically talking about what ends up being presented on github pages with markdown: kramdown

1. Expand/Collapse WORKS in general as a standalone, separate from any other markdown in the .md file

   <details> <summary>Spoiler</summary> my extra lines </details>
   

2. Expand/Collapse WORKS when Nesting details inside a markdown bullet:

   * <details> <summary>Spoiler</summary> my extra lines </details>
   

3. Expand/Collapse Does NOT work if details need to be a sub-bullet:

   * <details> <summary>Spoiler</summary>
       * my extra lines</details>
   

4. Formatting Does NOT work if details need to bold or code formatting:

   * <details> <summary>Spoiler</summary> my `extra` **lines** </details>
   

You can also put a <pre> inside the <details>

A collapsible section with markdown

Click to expand!

Heading

1. A numbered
2. list
   • With some
   • Sub bullets

A collapsible section with markdown

Click to expand!

def func():
    return 'hello, world!'

Super nice feature! ... except that the opened <summary> element is too narrow (has no margin) at the bottom, I feel.
I hope some kind of CSS like this is applied to GitHub for better appearance...

details[open] summary {
    margin-bottom: 16px;
}

Super nice feature! ... except that the opened <summary> element is too narrow (has no margin) at the bottom, I feel.
I hope some kind of CSS like this is applied to GitHub for better appearance...

details[open] summary {
    margin-bottom: 16px;
}

I use <br />&nbsp; at the end of my <summary> content to add an extra line of spacing. HTML works inside this tag. Give it a try.

It will be cool to have an attribute to indicate "default opened" but collapsible

It will be cool to have an attribute to indicate "default opened" but collapsible

This already exists:
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/details

Attribute: "open"

i.e.:

<details open>
    <summary>some summary</summary>
    some opened collapsible
</details>

some summary

some opened collapsible

some summary

> some opened collapsible

some summary

some opened collapsible

It would be nice to be able to use details in numbered and bulleted lists

@RomanSoloweow Looks ugly but works

<details>
<summary>some summary</summary>

A list
- Another list item
- <details><summary>some summary</summary>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc est tellus, convallis eget vulputate ut, eleifend vel mauris. Maecenas consequat aliquam tortor quis bibendum</details>
- Another list item

</details>

some summary

A list

• Another list item
• some summary

  Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc est tellus, convallis eget vulputate ut, eleifend vel mauris. Maecenas consequat aliquam tortor quis bibendum
• Another list item

I just wish that GitHub markdown made headings collapsible.

I have a problem on my website with this.
Normal text on my website is smaller than the text within the details. So, the text within "details" looks like 2+ pt bigger than the rest of the text on my site.
Does anyone know why? How can I fix this?

test

+ pp[p
- oo[o

Configuration example

{"a": "b"}

Can you use md markup for linking inside the <summary/> tag? It seems to work inside the <details/> tag.

@rubek-joshi It is possible but there is a catch, it can't be markdown formatting because a new line is required for markdown parsers to parse and render them.

So this is possible

Some bold text code.go link

func main() {}

But not with markdown but with HTML tags

<details><summary><s>Some</s> <b>bold</b> <i>text</i> <code>code.go</code> <a href="//example.com">link</a></summary>

    ```go
    func main() {}
    ```
</details>

can use markdown if you don't mind a newline in your summary link

interface{}

i.e.

<details><summary>

can use *markdown* ~if~ you don't mind a `newline` in _your_ summary [link](//example.com) </summary>
    ```go
    interface{}
    ```
</details>

You can go even crazier and have a multiline image, stack trace, etc. in the summary

slim (3.0.7) lib/slim/parser.rb:513:in syntax_error!' slim (3.0.7) lib/slim/parser.rb:259:inunknown_line_indicator'
slim (3.0.7) lib/slim/parser.rb:250:in parse_line_indicators' slim (3.0.7) lib/slim/parser.rb:192:inparse_line'
slim (3.0.7) lib/slim/parser.rb:95:in call' temple (0.7.7) lib/temple/engine.rb:50:inblock in call'
temple (0.7.7) lib/temple/engine.rb:50:in each' temple (0.7.7) lib/temple/engine.rb:50:ininject'
... show more

slim (3.0.7) lib/slim/parser.rb:513:in syntax_error!' slim (3.0.7) lib/slim/parser.rb:259:inunknown_line_indicator'
slim (3.0.7) lib/slim/parser.rb:250:in parse_line_indicators' slim (3.0.7) lib/slim/parser.rb:192:inparse_line'
slim (3.0.7) lib/slim/parser.rb:95:in call' temple (0.7.7) lib/temple/engine.rb:50:inblock in call'
temple (0.7.7) lib/temple/engine.rb:50:in each' temple (0.7.7) lib/temple/engine.rb:50:ininject'
temple (0.7.7) lib/temple/engine.rb:50:in call' temple (0.7.7) lib/temple/mixins/template.rb:10:incompile'
temple (0.7.7) lib/temple/templates/tilt.rb:30:in prepare' tilt (2.0.5) lib/tilt/template.rb:92:ininitialize'
sprockets (3.6.2) lib/sprockets/legacy_tilt_processor.rb:25:in new' sprockets (3.6.2) lib/sprockets/legacy_tilt_processor.rb:25:incall'
sprockets (3.6.2) lib/sprockets/processor_utils.rb:75:in call_processor' sprockets (3.6.2) lib/sprockets/processor_utils.rb:57:inblock in call_processors'
sprockets (3.6.2) lib/sprockets/processor_utils.rb:56:in reverse_each' sprockets (3.6.2) lib/sprockets/processor_utils.rb:56:incall_processors'
sprockets (3.6.2) lib/sprockets/loader.rb:134:in load_from_unloaded' sprockets (3.6.2) lib/sprockets/loader.rb:60:inblock in load'
sprockets (3.6.2) lib/sprockets/loader.rb:317:in fetch_asset_from_dependency_cache' sprockets (3.6.2) lib/sprockets/loader.rb:44:inload'
sprockets (3.6.2) lib/sprockets/cached_environment.rb:20:in block in initialize' sprockets (3.6.2) lib/sprockets/cached_environment.rb:47:inyield'
sprockets (3.6.2) lib/sprockets/cached_environment.rb:47:in load' sprockets (3.6.2) lib/sprockets/bundle.rb:23:inblock in call'
sprockets (3.6.2) lib/sprockets/utils.rb:196:in dfs' sprockets (3.6.2) lib/sprockets/bundle.rb:24:incall'
sprockets (3.6.2) lib/sprockets/processor_utils.rb:75:in call_processor' sprockets (3.6.2) lib/sprockets/processor_utils.rb:57:inblock in call_processors'
sprockets (3.6.2) lib/sprockets/processor_utils.rb:56:in reverse_each' sprockets (3.6.2) lib/sprockets/processor_utils.rb:56:incall_processors'
sprockets (3.6.2) lib/sprockets/loader.rb:134:in load_from_unloaded' sprockets (3.6.2) lib/sprockets/loader.rb:60:inblock in load'
sprockets (3.6.2) lib/sprockets/loader.rb:317:in fetch_asset_from_dependency_cache' sprockets (3.6.2) lib/sprockets/loader.rb:44:inload'
sprockets (3.6.2) lib/sprockets/cached_environment.rb:20:in block in initialize' sprockets (3.6.2) lib/sprockets/cached_environment.rb:47:inyield'
sprockets (3.6.2) lib/sprockets/cached_environment.rb:47:in load' sprockets (3.6.2) lib/sprockets/base.rb:66:infind_asset'

Like this

<details>
<summary>

![hek](https://picsum.photos/40/40)
    ```ruby
    slim (3.0.7) lib/slim/parser.rb:513:in syntax_error!' slim (3.0.7) lib/slim/parser.rb:259:inunknown_line_indicator'
    slim (3.0.7) lib/slim/parser.rb:250:in parse_line_indicators' slim (3.0.7) lib/slim/parser.rb:192:inparse_line'
    slim (3.0.7) lib/slim/parser.rb:95:in call' temple (0.7.7) lib/temple/engine.rb:50:inblock in call'
    temple (0.7.7) lib/temple/engine.rb:50:in each' temple (0.7.7) lib/temple/engine.rb:50:ininject'
    ... show more
    ```
</summary>
...
</details>

Is it possible to include (Python) code inside summary and serve it on a Jekyll site such that it holds onto the same formatting as a chunk of code that's not inside the summary tag?

So far I either get no formatting at all, or when using pre tag inside summary I get some default formatting but not the one of my style.

test

...this is hidden,collapsable content...

@TomasMiskov yes, but I had to do some digging to find what to do. It required a modification to _config.yml:

markdown: CommonMarkGhPages
commonmark:
  options: ["UNSAFE", "SMART", "FOOTNOTES"]
  extensions: ["strikethrough", "autolink", "table", "tagfilter"]

Which is in the docs by github here.

After I pushed up the above, I was able to do this in github.io pages and *.github.com:

Python3.10

Check out this bash syntax highlighted block:

  brew install python@3.10

  <details>
    <summary>Python3.10</summary>

    Below, you can change the first ``` to ```bash for syntax highlighting :)
    Checkout this regular code block:

    ```
    brew install python@3.10
    ```

  </details>

Here's an example of it working in jekyll.

Thanks @jessebot! In the end, I solved it by encapsulating the code in the Jekyll liquid tag like this:

{% highlight python %}

some code

{% endhighlight %}

More info here.

No problem! Also, thanks for the info on the highlight syntax for Jekyll! :)

Were you able to get that to work on github.com as well? I couldn't find a way that didn't show the {% highlight python %} start and end tag in the code block, but I'm relatively new to Jekyll.

Nested details:

• 1 1- Introduction

  • 1.1 Second Level 1

    • 1.1.1 Third 1a
    • 1.1.2 Third 2a
    • 1.1.3 Third 3a
  • 1.2 Second Level 2

    • 1.2.1 Third 1b
    • 1.2.2 Third 2b
    • 1.2.3 Third 3b
  • 1.5 Alone 1
  • 1.6 Alone 2

Code:

  * <details><summary>1 <a href="#cap1"> 1- Introduction</a></summary><ul>
     <li><details><summary> 1.1 <a href="cap1_1"> Second Level 1 </a> </summary> <ul> 
           <li>1.1.1 <a href="cap1_1_1"> Third 1a </a> </li>
           <li>1.1.2 <a href="cap1_1_2"> Third 2a</a> </li>
           <li>1.1.3 <a href="cap1_1_3"> Third 3a</a> </li>
     </ul></details></li> <!-- End 1 -->
     <li><details><summary> 1.2 <a href="cap1_2"> Second Level 2 </a> </summary> <ul> 
           <li>1.2.1 <a href="cap1_2_1"> Third 1b</a> </li>
           <li>1.2.2 <a href="cap1_2_1"> Third 2b</a> </li>
           <li>1.2.3 <a href="cap1_2_1"> Third 3b</a> </li>
     </ul></details></li> <!-- End  2-->
     <li>1.5 <a href="cap1_5"> Alone 1</a> </li>
     <li>1.6 <a href="cap1_6"> Alone 2</a> </li>
   </ul> <!-- End -->
  </details>

Level 1

Level 2

Level 3

Last Level

#include <bits/stdc++.h>
int main() {
    cout << "Hello World";
}

Level 1

Level 2

Level 3

Last Level

#include <bits/stdc++.h>
int main() {
    cout << "Hello World";
}

Level 1

Level 2

Level 3

Last Level

#include <bits/stdc++.h>
int main() {
    cout << "Hello World";
}

Level 1

Level 2

Level 3

Last Level

#include <bits/stdc++.h>
int main() {
    cout << "Hello World";
}

Level 1

Level 2

Level 3

Last Level

#include <bits/stdc++.h>
int main() {
    cout << "Hello World";
}

Does anyone know how to use an image as a summary of details element?

On click of image, I want to expand.

---

foo bar

😩