https://netflixtechblog.com/enhancing-the-netflix-ui-experience-with-hdr-1e7... referenced in https://www.collabora.com/news-and-blog/news-and-events/breakthroughs-open-s... technically, cinelerra does have pop up menu in fullscreen (compositor/viewer) mode, but I guess caring about it being correctly blended into HDR image is one of our least worries .....