We knew it was coming and in the latest leaked build of Windows 10, FLAC playback is now supported natively in Windows Media Player which joins MKV in new media support for the OS



From Neowin:

FLAC stands for 'Free Lossless Audio Codec' and can shrink a file to roughly 50-60% of its original size; when decompressed the file goes back to its original state. It's important to note that this is OS level support, so any Win32 or modern app will be able to take advantage of this feature.

This additional codec is not the only new media support coming to Windows 10; Neowin had uncovered that MKV support will also ship with Windows 10 as well.

  Windows 10: 9901 has native FLAC support