After extensive testing and fixing bugs identified in the first Mautic 3 beta, we have made available a second beta for community testing which you can download at https://github.com/mautic/mautic/releases/tag/3.0.0-beta2.
Please note this is for testing purposes only and not for use in a production environment at this stage.
We are planning a stable release at the end of the month, assuming no major issues are identified during the testing of this second beta release.
Mautic 3 has been a 5 month project which has touched every part of Mautic and included 2800+ commits, 3900+ changed files, 230000+ insertions, 97000+ deletions. Read more: https://www.mautic.org/blog/community/mautic-3-is-coming.