Sorry for the inconvenience caused. Can you please share you monitor details. Are using a 4 k machine? On which version of Illustrator are you working on now? Please share this details it may help us to reproduce the issue .
An error occurred while saving the commentMagda commented
i have the same problem, I work on Mac OS and have 2nd monitor connected - if i disconnect this and use only IMac there is no problem... but i want use two displays at the same time :/