One of the most annoying aspects of Windows after using Linux on the desktop for 10+ years was how the mouse wheel scrolled windows.
On Linux desktops I could hover over a window and scroll it without focusing. It was really useful when I had a browser window with instructions behind a terminal or just comparing the contents of two windows. The same happened when scrolling panes in file managers. I could scroll directories when hovered over that side of the window and files when over on the other..
So, imagine my frustration when I realised I had to click the side of the Explorer window I wanted to scroll in Windows? It was doubly annoying if I had selected files as I’d have to click an empty area or CTRL click an already selected file to select that side of the window.