yeah, SU23 moved to a new framework, QT, for its interface. Turns out QT contains not only up and down screll, but also side scroll.
the vast majority of mice don’t have side scroll, but a handful, including a handful of microsoft ones, do.
you should check this thread (this message and the next cover microsoft)
people are discussing solutions, between updating the drivers, deactivating the sidescroll in a mouse-managing software, to typing a few lines of code.