The original project, https://github.com/FokkeZB/J2M is now unmaintained. It runs at http://j2m.fokkezb.nl There are a few forks of the original that have some interesting content
- https://github.com/deng78/J2M
- Support to parse jira @mentions
- https://github.com/rossmd/J2M
- multi level bulleted lists
- https://github.com/egsy/jira-md
- dockerized
- https://github.com/macintacos/J2M/
- ran through prettier, some fixes
@kylefarris also forked it and did large rewrite. Since then, a number of people have forked his fork and added fixes and features
https://github.com/kylefarris/J2M
- https://github.com/duhruh/J2M
- adds support for images
- strikethrough changes
- named/unnamed code block changes
- move table creation earlier in parse sequence
- https://github.com/karimatthews/J2M
- fix strikethrough
- bugfix intra-word underscores and asterisk
- lots of edge cases for bold and italic
- https://github.com/gmaxdm/J2M
- fix strikethrough
- bugfix named links
- https://github.com/peterfotinis/J2M
- bugfix un-named links, italic, bold
- https://github.com/cookielab/J2M
- add support for images
- fix un-named links
- add panel
There are other forks which I've not looked into completely as they all have their newest commits older than when the original project went unmaintained.