Arduino Running Slow - Beachballing on a Mac

I've been using Arduino on a Mac for about three months. I decided to uninstall and reinstall it due to some problems, and now it is beachballing constantly, and it takes 30-45 seconds to load. All other apps on my Mac run fine.

Any thoughts?

Did you change versions of the Arduino IDE?

Is it only unexpectedly slow on startup, or other times also?