Letterbox / output blanking
I'd like to suggest a new feature that allows users to use output blanking into both the timeline monitor and source monitor. This feature would be particularly useful for those working on 16:9 projects and timelines and with a blackmagic playback, enabling them to seamlessly add (for exemple) a 2.39 aspect ratio letterbox overlay to both monitors. Additionally, enhancing user control, it would be beneficial to have the ability to adjust the opacity of the overlay for added flexibility.
