Horizontal scrolling with mouse wheel is reversed
I have a Dell MS7421W wireless mouse which has a four-direction wheel.
On Windows when we scroll the wheel forwards, the view port and scroll bar of the target window goes upwards (text goes downwards), and when we scroll the wheel backwards, the view port and scroll bar goes downwards (text goes upwards). So it's reasonable to predict that if we nudge the wheel to the left the horizontal scroll bar should go left (text goes right), but it's not the case in Notepad3: Nudging the wheel to the left actually scrolls to the right. It had better to match other applications, such as Visual Studio and Excel.
It looks like it's a duplicate of: #5020
Yes, possibly. It's natural to have touchpad and mouse wheels set in mutually reverse directions as mentioned in the other topic, but my laptop runs Linux so I can't test it. Sorry.