I have multiple monitors in different resolutions: 1440p for my main screen and 1080p for my side screen. I use the vertical view setting. The message preview width seems to be fixed to what you set it. This causes the message list or card view to scale to fill up the width. When I set the column widths to be good for 1440p, this will make the message list very small on 1080p. And when I set it up for 1080p, the message list becomes really wide for 1440p. So constantly keep adjusting column widths when changing the window size. Pretty annoying.

It would be a lot better if the message list and message preview pane would both scale their width to fill up the available width.