Yup: all the animation stops, the overlaid snowflakes disappear, and the background changes from blue to yellow. I haven't bothered to check the foreground/background contrast of the two versions, but I suspect that, although the yellow version will have less contrast, the removal of the snowflakes will make for a net benefit to readability for the average person.

This is the biggest mistake, imo. The snowflakes should disappear immediately...