[sprash]

Taking screenshots/streaming is not a hard problem. However Wayland artificially turns something as simple as taking a screenshot into a hard problem what was before a simple function call to XGetImage(). As exercise I recommend to implement a native screenshot application in both X11 and Wayland.

[marcodiego]

I think you're completely ignoring the security implications of "a simple function call to XGetImage()".

[sprash]

What are the security implications? Programs that call XGetImage() when sandboxed in a Xpra/Xephyr session will get back nothing.

[marcodiego]

Will get nothing... that means the screenshot won't be taken.