You say it's not a "bug" that the video switches to monoscopic display while the UI menu is open, to prevent dizziness, but opening the menu for any reason and having the video defocus, agitates my eyes very much.
I at least want the "option" to keep the video in stereo while the UI is up.
I consider mono-UI being "broken", so at one point it was "fixed", then one day it just broke for a while until something happened, and it was fixed again, then later it would "sometimes break" until I found out it only happened when videos were set to a specific stereo mode. Then today when I clicked reset on the video transforms, it broke again and I couldn't find out how to "fix" it again.
I'm trying to find a way to "trick skybox" into displaying videos in Stereo while the UI is open again
but a far better option would be for you to to make that a feature and not a (welcomed) bug.