Normally, there are 6 methods to fix the WindowServer Mac high CPU problem: Method 1: Minimize the number of files & folders saved on your desktop. Method 2: Quit all unnecessary apps and windows. Method 3: Switch off transparent effects on your Mac. Method 4: Prevent Mission Control Spaces from rearranging itself. Method 5: Disable 'Displays have separate Spaces' in Mission Control Method 6: Restart your Mac