Vertical fitting of the camera frame in viewport

I noticed that if the camera frame is set to portrait, like lets say 9:16, then when you load the saved blend file, the margins of the camera are cut so that the left and right are fit, BUT the top and bottom are totally cut off. We need fitting based on also vertical edges. Cause if not, you always have to unlock the camera, zoom out, and lock it again. Tedious and unnecessary.