No,
Activity stream is designed as a Chat interface, just to enter text.
But you can enter notes, with Rich Text Edito, they will appear in Activity Stream.

Ok. Could this be a possible future "evolution"?

Most modern chat system I know like MatterMost or Matrix/Element allow text formatting with Markdown markup, and other issue management / ticket systems do similar, like GitHub tickets (also with Markdown) or Jira (with its own markup codes), while still providing an "Activity Stream" like presentation.

It'd be especially handy to be able to make URLs clickable or for adding emphasizes or small lists.

(In general I'd consider it to be quite helpful if URLs would automatically be converted to links, possibly as some kind of post-processing before saving them to the DB, as most users are used to this behaviour from mail clients, wiki systems and also most of the software mentioned above. It's a bit cumbersome to manually add links to every URL I include in an object's description or note...)

Could this be a possible future "evolution"?

No, it's not is the purpose of Activity Stream

Most modern chat system I know like MatterMost or Matrix/Element allow text formatting with Markdown markup

But projeqtor is not a chat system.
It's a project management tool 😉
Markdown system would involve heavy coding to store text that can be read in notes, with html formating : so we'd have to ensure consistency between html dis^lay/coding and makdown display/coding. A real mess I don't want to enter into.
You already have notes to enter rich text formating. Just use it if you need some formating.

It'd be especially handy to be able to make URLs clickable or for adding emphasizes or small lists.

Notes system allow url formating 😉

But projeqtor is not a chat system.

Well, just in your previous message you wrote:

Activity stream is designed as a Chat interface, just to enter text.

That's why I was referring to chat systems. 🙂

Ok, I understand that you don't consider "rich text" support in the activity stream input box to be needed, so I don't want to push this.

However, just out of curiosity:

Markdown system would involve heavy coding to store text that can be read in notes, with html formating : so we'd have to ensure consistency between html dis^lay/coding and makdown display/coding. A real mess I don't want to enter into.

I think CKeditor works on the HTML DOM and you're probably storing HTML internally - is this the case? If so, then I'd expect it only to be necessary to convert Markdown to HTML (eg. https://github.com/erusev/parsedown, FOSS under MIT license) once, when it's entered - afterwards, it will already be in the proper format for CKeditor if the note is edited again.

Hi,

I tested Parsedown.
Seems interesting, so idea is simply to convert text with markdown into html.
As long as we don't have to "edit" the markdown syntax, it seems not so complicated as I first imagined.

Have to do more tests as I faced several "unexpected extra blank lines", for instance with lists.
Ticket #4914