I also concur @ouroumov that it could be a hardware fault.
I had the opposite problem a long while back where the mouse had random clicks… after cleaning the mouse buttons, it hasn’t happened since… just coincidence the system had updates.
Trackpads in my experience could act funny too if there’s dust, fingermarks or pressure on the surface making the hardware believe a finger is “tap and holding” a click, like here. Try giving the surface a good clean and check there isn’t pressure on one side of the touch pad.