I believe this is a setting on your system, i can drag the viewport bigger in all direction, in edit mode i can add extra node's and select several nodes in one time for moving together or deleting, when selecting several nodes it works in the same way like the "stretch tool" make a selection fence over it and use the Shift to make more selections.
V18, V19, V20, V21, 2015/ 16/ 17/ 18 Pro. Platinum
Deluxe V20, V21, 2015/ 16/ 17
Windows 10 Home Premium 64 bit, 32 GB
NVIDIA Geforce GTX 780m, 1 GB