I had the same issue of my screen freezing every time I used an ability, I tried using CPU profiling to pinpoint which addon was suddenly slowing me down, but I got a different result each time.
It went away after disabling w/e addon I thought was causing it, but considering I disabled different addons each time, it was probably just the reload that helped.
I use 10s of addons, so if this is an addon problem, I'd have quite a time finding it
