Filing this bug report again. Often, the Shift wheel mode will switch on my mouse. I don't have any buttons assigned to it. So toggling it back requires me to change one of my buttons to "shift wheel mode", then switch the button functionality back.

This happens a couple times a month. Often after the the Logi+ app updates or crashes or restarts.

A useful fix would be to make the shift wheel mode a setting outside the buttons. I would permanently disable the ability to switch modes.