I usually refresh the page if a pet gets frozen while exploring but then it started doing this weird thing where I would hit the arrow key to move, the "log" would update about picking up an item, but on the map my pet hasn't moved. I've done it twice now and no matter how often I refresh the page it keeps doing it.

Also, I'm using a Mac with the latest update on it (10.7.5) if that makes any difference.

Edit: just tried it with two other pets and the same thing happens.

Edit again: seems to be working now. I'm not sure what happened before but just wanted to note it.

It might be due to a slow/unstable connection? o:
Same thing happened to me when I was using my phone's tethering.
After a while, my pet suddenly took a diagonal leap to where it's actual location was.