The new icon grid layout operates based on rows and columns, and
doesn't try to dynamically adapt it to fit to the container. In
this case, it is better to have a pre-defined set of well-known,
well-tested rows and columns, and switch between them based on
the aspect ratio of the screen.
Introduce a set of modes to the icon grid, and select the mode
that is closest to the aspect ratio.
https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1271
c5dbdad5fc