I've noticed that my start menu, notification bar and right mouse menu activate on their own, in a very random manner; I haven't figured out what would be triggering it, or been able to intentionally reproduce it. This happens when I'm browsing the web, watching a movie, or just doing some document editing. This has happened maybe about a dozen times over the past year. I'm certain that I'm not touching any keypad buttons or touchpad that could trigger this. I have scanned it with Malwarebytes and Avira AV and all comes back clean. The system has the latest updates as well.
What could this be then?