Chosen Solution
Several keyboards and mouses I try that are wired or bluetooth keep actin erratically and jumping across the screen. both bluetooth and wired– and several. i’ve tried reinstalling macOS and tried test user and it is system wide and very beyond annoying. the internal keyboard and trackpad work fine. i need the external keyboard and mouse because the screen is cracked and i use the mac in clamshell mode your thoughts and insights to fix this?
You may have a swelled battery which is pressing on the internal keyboards and/o trackpad cables. Let’s get a better view of things, install this gem of an app! CoconutBattery take a snapshot of the apps main window and post it here for us to see Adding images to an existing question
