JForum2
Bug fixes and enhancements for JForum 2.x
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There is extensive documentation of all aspects of the software at https://sourceforge.net/p/jforum2/wiki2/Home/
Source code and a beta build are available for running JForum on JakartaEE 10 environments such as Tomcat 10.1; it requires Java 11. This has not been tested as extensively, and remains work in progress.
It is freely available under the BSD license, and has recently been awarded the SourceForge "Community Choice" badge.