Github Flavored Markdown Alerts == Admonishions

[oxinabox]

GitHub recently added what they term "alerts" to their markdown.
It is described here in the github docs
though it is not in the GFM spec

they are basically the same as our Admonishions extension.

We should support them also, at least with the github flavor set

[jonas-schulze]

They changed the syntax as well. I did not know that the previous syntax,

> **Warning**
> Critical content demanding immediate user attention due to potential risks.

was part of a beta period, or subject to change.
The old syntax looked ok even on GitLab, while the new syntax

> [!WARNING]
> Critical content demanding immediate user attention due to potential risks.

is rendered verbatim. 😕