Alexa, take a screenshot.
Would be helpful in documentation and marketing/promotion of APL-driven skills to be able to take a screenshot directly off the device.
Saying something like "Alexa, take a screenshot" could take the screenshot and save it to Amazon Photos, just as "take a selfie" does with the front-facing camera.
Patrick Hawks commented
When I tell my Echo Show "take a screenshot," it makes a sound like it understands the request, but I cannot find the screenshot anywhere in Amazon Photos.