The current default action for the mouse scroll-wheel is zoom in/out in PulseView (which is perfect). Additionally, it would also be nice to be able to scroll vertically (e.g. if you have many channels/traces). This could be done e.g. by holding/pressing a key (say CTRL) while using the mouse scroll-wheel.
Implemented in 208c6fc371951fe74ba5a08a0950f2837eef8b7b, thanks!