I'm aware that MS Project does not allow you to have multiple instances of the application open unlike the rest of MS Office. I know that you can view multiple projects at once by clicking the Arrange All button in Window group of the View Tab
When I click the button, it stacks the project files on top of each other like this:
However, I want the button to arrange them side-by-side, like this:
I can't seem to find a way to do this automatically. I always need to resize and reposition the windows manually. What setting do I need to change to make this happen? I've tried clicking the arrange all button twice, but it does not change the orientation of the windows. I know it's possible because I've seen other MS Project users do it. I'm using MS Project Professional 2016.