Last week, when I was listening to a podcast on my Surface Pro 3, the podcast randomly paused, most likely because someone clicked the pause button, then the pointer was moving by itself and opening tabs in Firefox (no mouse or trackpad were plugged in). I didn't bother, I just restored the computer, and haven't used it since then. Being a little too paranoid, I also did reset my modem and router, so everything would be fresh.
Today, my new computer did the exact same thing, it paused my Youtube video and the cursor started moving by itself. I turned it off and booted in safe mode and made several antivirus scan with different programs (Norton, AVG, CCleaner, Malwarebytes), and nothing suspicious came out.
What the deuce is going on? Could maybe this has to do with a malicious Firefox extension?
PS: I am using legitimate copies of Windows 8.1 Pro.