I am really confused about the releases of discourse. Last time I was upgrading my forum, I was deploying v.2.5.6 when v.2.6.0 was already out. This was due to me looking for the releases tab of github:
How is this possible?
How does one know what’s the latest stable release?
Since then we moved to Ruby 2.7 in production, but Discourse 2.5 was not compatible with Ruby 2.7. Discourse 2.5.6 is just 2.5.5 with backported Ruby 2.7 compatibility, as your can check for yourself in the commit logs.