Comment 9 for bug 786317

Yeah, I'm having the same exact issue. I can also confirm that deactivating the stylus does fix the "stickiness". I have not tried running in Ubuntu classic without effects yet. I did however try turning off various effects, but wasn't able to find one that restored the correct behaviour (I didn't try all, admittedly though).

I have noticed that sometimes, the problem will go away after a while, and it's hard to say what causes that.