I have MacBook Air, 13 inches, macOS Sierra. Version 10.12.5
Sometimes when I put mouse over or click on some text - the area where mouse pointing getting red, sometimes this red area is getting bigger and started blinking and looks like those changings on screen are nor related to mouse.
It happened once a week and I could not tell what trigger this. I was told by Mac representative that this is probably some sort of malware.
But I have application Adware Medic and it doesn't detect any malware.
I think that it is possible hardware issue.
Any suggestion what cause this issue and how to fix it?
//EDITED Sometimes I have no red (see pictures below):