Today we release Serendipity 2.6-beta1!
The main advantage this time might be support for PHP 8.4 - if you need a serendipity version that works with PHP 8.4, you should use this beta even on a production blog. It has also a couple of other fixes, upgrades to bundles libraries and new features like the support for receiving webmentions and a faster integrated cache. But it's still a beta, additional testing is needed to make this version a proper stable release, so stick to test environments if in doubt.
Please help us in making the 2.6 stable release soon by reporting bugs and issues, or even better by providing patches to Github (the core or the plugins).