HTML tags <details> and <summary> are removed / don't work

[Schmuuu]

Hi,

I would like to create an FAQ with all the questions and when you click them, the answer in form of a text block will expand below this question. Before HTML5 this was usually achieved by Java script.

Now trying out Pico CMS I would like to go without any Java script and use only HTML5 instead.
The following works on a "normal" web page:

<details>
<summary>Short text</summary>
<p>Long, hidden text, that unfolds if visitor clicks on the summary text</p>
</details>

But using this in cms_pico these tags (details and summary) are removed on the web site and consequently there is no hidden text that unfolds/ expands.

Could these tags please be kept and not filtered out?

Thanks a lot.

Serverinfo:
Nextcloud 12.3
cms_pico 0.9.6
nginx 1.12
PHP 7.1

[ArtificialOwl]

you will need to implement a plugin to generate those tags, and parse the html to remove any malicious javascript

[Schmuuu]

ehm and how?
I consulted the pico team (https://github.com/picocms/Pico/) first (via their IRC channel actually) and they assured me that HTML5 tags work with Pico and it must be the Nextcloud app filtering these tags.

I got the impression that I enable the app and I'm ready to go. Where do I get such plugin and how to I implement it?

[ArtificialOwl]

Please ckeck this page to understand why the app filters those tags.

[Schmuuu]

Thanks for the link. I checked that site before and totally understand that.
However I'm wondering where the security risk is with these html tags.

https://www.w3schools.com/TAGS/tag_details.asp
For me it seems to be an html tag just like <p>, <div>, <h1> and so on.

My current page looks like this:

<h1>Frequently asked questions</h1>
</header>
<h2>General</h2>

<details open="open">
<summary>Little summary</summary>
<p>This is the content</p>
</details>

Every other tag works, only these html5 tags don't.
I already saw, that there are javascript files, that seem to handle html tags, but they are unreadable, because it's a huge one-liner.
Any help is appreciated.

[Schmuuu]

Thank you!!