Vertical 9/16 resolution for video clean feed

When editing in a vertical resolution project, DR will still output a 16:9 video clean feed to a secondary monitor. Even when the secondary monitor is set up as vertical in macos system preferences. How is that even possible?

How is that even possible?

How are your settings in Image Scaling -> Output Scaling set up? I assume you don't actually have a 9x16 monitor (or maybe you do), but I bet you could set a custom Output Resolution setting and it should "just work."

We had a whole bunch of projects destined for Snapchat some months ago, and we were able to view and optimize them for 1080x1920 without any real problem. We did have some back-and-forth discussions with the client on color and brightness, but image size was never a problem.

Thank you for your reply, Marc. It seems like the timeline settings are ignored, even when the projects settings say otherwise. But entering a custom resolution in the project settings did the trick

So the feature request would rather be a bug fix, imho