The release candidate for 3.9.8 is here 
https://github.com/getkirby/kirby/releases/tag/3.9.8-rc.1
Even though this is very likely the last 3.9 release, it comes with some features and enhancements.
Again, it’s helping with v4 because we constantly merge the latest 3.9.x stage into v4. All of the stuff in the release notes is either already available in 4.0.0-beta.3 or will be in the next v4 release.
The stable release will follow next week. Please, help us test this if you find the time.
We thought for a while how we could handle PHP 8.3 support in v3. Some of our dependencies unfortunately make a hard cut and drop PHP 8.0 support with support for PHP 8.3. That’s why we decided to not support PHP 8.3 in Kirby 3.9. Instead, we will release 3.10 together with Kirby 4. This will be just a PHP 8.3 support release.
3.9 will support PHP 8.0 until 8.2
3.10 will support PHP 8.1 until 8.3
There won’t be any other differences between 3.9 and 3.10. But for your old projects, this will increase the range of supported PHP versions and will give you more freedom depending on your hosting environments.