Markdown flavors
Gitlab flavored markdown (gfm)
See also
https://commonmark.org/
https://talk.commonmark.org/
https://github.com/commonmark
https://github.com/commonmark/commonmark-spec
https://github.com/commonmark/commonmark-spec/wiki/List-of-CommonMark-Implementations
https://github.com/readthedocs/commonmark.py