We reccommend all front ends support markdown. The specific markdown you allow may vary, but your markdown parser should be able to handle all of the following.
# Inline
*italics*
_italics_
**bold**
__underline__
# Heading
## Levels
### One
#### Through
##### Heading
##### Level
###### six
#tags
:emojis:
\*escape sequences\*
[inline links](LINK)
![images](source)
> Blockquotes
`inline code blocks`
``inline code blocks``
(multi line code blocks, with language support)
Additionallyt, we reccommend it supports the following:
---
frontmater: keys
---
[id links][id]
[id]: URL
> [!type] callouts
> with cudstom titles and full markdown supported inside.
horisontal rules
---
and the abbility to add custom stuff for
@user@instance.tld chips
#channel@groupid@instance.tld chips
For messages, we reccommend you only allow inline, links, images, code, tags, and emojis, but other channel types will likely want more advanced markdown such as wiki channels