Enthusiasts demonstrated the ability to boot Windows 10 from a partition with the Btrfs file system. Support for Btrfs was provided through the open-source WinBtrfs driver, which proved to be sufficient to completely replace NTFS. To boot Windows directly from the Btrfs partition, the open bootloader Quibble was used.
In practice, the use of Btrfs for Windows is relevant to save disk space in dual-boot systems, since the contents of Linux and Windows environments do not overlap at the level of base directory names, and both environments can be placed in one shared file system without using separate partitions. The Windows system environment was transferred to Btrfs from the original NTFS partition using the Ntfs2btrfs utility, after which Arch Linux was additionally installed on this Btrfs partition using the pacstrap utility.
Source: opennet.ru