Anna, I too switched to Firefox and it works great. Like they say when making online transactions, only hit the button one time. I don't even trust the spinning "busy" , or lack of it, when loading a puzzle. If it does not load immediately, I go to "recent games" and scroll to the bottom to make sure. I keep a separate tab open on cryptograms specifically for this purpose. I also use the separate tab to check scores, in case I want to go back to the puzzle I just solved, as you can no longer use the browser "back" button.
My goal is 100% solve rate, so I keep working on a puzzle, no matter how long it takes. Average score is my secondary goal (which is affected by some of my very slow solve times).