2 versions of cordova-ios: v5.* and v6.* have different screen sizes even though tested on 1 device

Question

I added and compared 2 versions of cordova-ios: v5.1.1 and v6.0.0 on same device: ipad pro 10.5 And I can see the difference in app size between v5.1.1 (768x1024) & v6.0.0 (834x1112)

v5_1_1.png

v6_0_0.png

So my questions are:

1. why is there a difference in this app screen size?
2. is there a way to fix the size 768X1024 for v6.0.0?