Catalina OS window on main screen

Hi JosanM, 

Thank you for posting in the Apple Support Communities. I understand you are having some issues with your MacBook Air’s display. 

Part of your issue appears to be image persistence. 

“Fixing image persistence

If you see a persistent image on your screen, you can use the screen saver to eliminate it:

• From the Apple menu, choose System Preferences, and then click Desktop & Screen Saver.
• Click the Screen Saver tab.
• Choose the screen saver you’d like to use.
• Use the menu next to "Start after” to select an interval shorter than the interval you set for display sleep and computer sleep in the Energy Saver section of System Preferences.
• To clear the persistent image, allow the screen saver to run for approximately as long as the image was displayed.“

You’ll find more information concerning image persistence here: Avoiding image persistence on Apple displays

If these steps don’t resolve your issue, you may want to Contact Apple Support

I hope this has been helpful.

Cheers!