Windows’ infamous Blue Screen of Death (BSOD) is turning a shade of green for Windows 10 testers soon. A leaked preview build of Windows 10 (build 14997) emerged on the internet earlier this week, and it includes a number of new features and changes. One of the biggest is a Green Screen of Death instead of the regular BSOD. Microsoft employee Matthijs Hoekstra teased the change on Twitter, and MSPoweruser reports that it was eventually discovered by Twitter user Chris123NT.

It’s not clear why Microsoft has picked green over blue for its Windows 10 Insider builds, but Hoekstra confirms this new color scheme is only for preview participants. It’s likely that Microsoft wants to distinguish between genuine BSOD issues and problems and crashes that are more likely to occur during the testing of Windows 10 builds. A number of Windows 10 preview users publish issues like BSODs publicly on blogs or social networks, and turning the color green will help Microsoft identify them during the test phase. Microsoft last updated the BSOD with QR codes, years after adding a frowning face for Windows 8.

Microsoft has put its public testing of Windows 10 on hold for the festive period, and the company isn’t planning to introduce any new builds until next month. The leaked 14997 build also includes options to enable Cortana during the initial PC setup phase, a F.lux-like blue light reduction feature, traces of an Xbox Game Mode, Microsoft Edge tab improvements, and app folders for the Start Menu.