Linux kernel 5.15 arrived on Halloween with many great new features, such as a brand new NTFS file system implementation contributed by Parangon Software to finally provide Linux users with fully functional NTFS support, realtime preemption locking, in-kernel SMB3 server, as well as DAMON (Data Access MONitor).
On top of all that, Linux 5.15 is an LTS (Long-Term Support) kernel branch, which will be supported for at least a couple of years. As usual, Collabora have made some important contributions themselves to the Linux 5.15 LTS kernel series.