Previous versions of Forgejo, as well as current versions of Gitea, support so-called external renderers.
It was removed from Forgejo docs; the question is whether the functionality is present.

• [ ] Find out if the current version of Forgejo supports external renderers.
• [ ] If it is possible, update the app.ini and test in the staging deployment

Example of external renderer configuration:

```
[markup.asciidoc]
ENABLED = true
FILE_EXTENSIONS = .adoc,.asciidoc
RENDER_COMMAND = "asciidoctor s -a showtitle --out-file= -"
; Input is not a standard input but a file
IS_INPUT_FILE = false
```