You made me doubt what I wrote.. so I tested it just now ;)
I can confirm that my git2 crops pixels when switching from 4:3 to 16:9.
Tested with these 6 resolutions:
1440x1080, 4:3
1920x1080, 16:9
1920x1440, 4:3
2560x1440, 16:9
2880x2160, 4:3
3840x2160, 16:9
Its most apparent when you...