Two small annoyances gone.
The tiny green shimmer on the bottom edge of the video is fixed. The decoder stores the picture in a slightly taller surface and the filter on the last screen line was blending real pixels with the uninitialized rows below it, which showed as one or two flickering green lines. Sampling is now clamped to the visible picture.
Joy-Cons reconnect properly. Detaching them during a game left input dead even after reattaching, until an unrelated controller pairing happened to revive it. The app now follows controller changes and re-opens the primary controller whenever the console reassigns it, so detach and reattach just works, for Pro Controllers too.
Both reported by @Lfer01 in #39 and #38.
Install
Copy green-nx.nro to sdmc:/switch/ (overwrite the old one) and relaunch.