You can download a first public testing release for the version 2.4 on Github. I made several fresh installations and also a few updates from version 2.3.5 and 220.127.116.11. Please test the new version and report errors, unexpected behaviours and inconsistency. Reports may go to the issue tracker on Github or, when you have no Github-account (what is most likely), as always to this forum.
Changelog can be seen on the above linked release page or in the file CHANGELOG.
Notes for updaters
If you want to test an update of an existing installation, please make a backup of the database and the installation itself before --or better-- make a parallel test installation of your existing version and upgrade the test- instead your live-forum.
Attention: The update is only possible when the existing installation is a version 2.3.5 or higher!
Attention: Use the update file
Trenne niemals Müll, denn er hat nur eine Silbe!