Bottom of screen is unavailable in stacking mode

[bdcarr]

Distribution (run cat /etc/os-release): Fedora 32 (Workstation Edition)

Related Application and/or Package Version (run apt policy pop-shell or provide the latest commit if building locally): 9e8ab29cb976b078aa6e8fab59b09527a092a1b8

Issue/Bug Description:
I've seen a few people post about this issue specifically for their terminals, but this is affecting every window for me. If I move/resize a window in stacking mode, there's a space at the bottom of the screen that the window can never move into. The space is about half the size of the row increment when resizing/moving a window, so I suspect this is to do with my screen resolution / DPI. Maybe if the amount of space left on the screen is less than a full row, it won't move into it?

Here you can see an example - the windows on the left have been arranged in auto-tile mode, which has no problem utilising the full screen. I then entered stacking mode and resized the right-hand window:

Steps to reproduce (if you know):
This is on a 1920x1080, 15.6" monitor

1. Enter stacking mode
2. Enter adjustment mode
3. Attempt to resize or move a window so it touches the bottom of the screen

Expected behavior:
The window touches the bottom of the screen, like it does in auto-tiling mode.