Illustrator - High CPU usage for no apparent reason.

Hey everyone.

This morning I am completely lost with a problem that makes absolutely no sense. One of my users here had Illustrator CC 2018 installed on her computer yesterday, and when we open it, the CPU Usage % keeps climbing, and climbing, and climbing, and climbing,... until it reaches around 109% CPU.

It's the first time I see something like this. Makes absolutely no sense to me. She has CS5 before on her mac and never once something like this happened. She's using a mid 2011 iMac, i5 with 12 gb of RAM, and whatever the best graphic card was at the time. It's a pretty decent computer, so I don't see why this would be happening. There's obviously something wrong with the software at this point.

Did somebody else witness this kind of behavior with Illstrator CC 2018 ?

Thanks !