Unity 5.3 is Slower on WebGL and iPad

Hi, I have just updated to Unity 5.3 and everything runs significantly slower on moderate to lower end devices and on WebGL. I used to get 60 FPS on WebGL. Without changing a single line of code I now get 40 FPS. Almost the same thing is happening on iPad3 where I get around 10 FPS less than before. Again, no code has been changed. What can be the reason behind it and how can I fix it?