[tombrossman]

> And yet basic video and screen capture is not working for years now. Arbitrary rectangle capture still doesn't work on Ubuntu 16.04 in any tool I know of.

I'm curious, what tools have you tried? I ask because the default screenshot tool works perfectly for stills (including stills of video playing in a window or full-screen), and the few video screen recording tools I've tried all worked perfectly. At the moment I'm using Kazam on 16.04 with the default Nouveau drivers, and a quick test with Chromium playing a video stream + Totem simultaneously playing a local video file confirms that everything is captured no problem. Full screen, arbitrary windows, all tested and working.

Tl;dr try Kazam, unless I'm misunderstanding the issue you describe?