Ever since booting up today, mouse wheel events in Plasma 5 sometimes get sent to the wrong window.
When I use the mouse wheel to scroll the content in any window that allows scrolling, scrolling will work for some time until suddenly, quite randomly, some other open window will start scrolling. For example, when scrolling in Firefox, suddenly instead of the Firefox window keeping on scrolling, the Konsole window next to it will scroll through its command history. A lot of the time, the scroll events seem to erroneously go to the window list or the desktop, meaning I end up switching through the open windows or the virtual desktops.
This only started happening today, but unfortunately, I cannot say which update might have brought this on, since I hadn’t rebooted in some time (weeks, maybe a month) before that. (I am using OpenSuse in VirtualBox, and I usually just freeze the VM instead of doing a real shutdown. I did a real shutdown yesterday because there was a kernel update.)
This is quite annoying, to the point where it kills the usefulness of the mouse scroll wheel entirely for me.