If you want to enlarge the Computer sidebar, once you see the two arrows click.
The window itself is now enlarged, but the border stays.
Now drag the border with the two arrows where you want it, larger or smaller.
Release the mouse button and you are set.
If the sidebar is still too small, repeat.
It's not optimal, but it's really complicated to change, for something you do maybe only once.
Values are probably stored when you do File Exit, or immediately, I'm not sure.
The window itself is now enlarged, but the border stays.
Now drag the border with the two arrows where you want it, larger or smaller.
Release the mouse button and you are set.
If the sidebar is still too small, repeat.
It's not optimal, but it's really complicated to change, for something you do maybe only once.
Values are probably stored when you do File Exit, or immediately, I'm not sure.