You might get a better response within the Developers area of this forum (you're on the user side, not the Developers). But when I need a screenshot I simply use my phone camera. I realize it's not as screen perfect as a screenshot, but it's quick and easy.
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution."
If you appreciate my answer, maybe give me a Kudo.
I am not a Roku employee, just another user.