Yep, it's Firefox 35.
As mentioned:
[quote:3oei6uaq] I'm sure about that since I did not touch the game at all and from one day to another, suddenly the shader effects were quite problematic.
In my case, light objects (WebGL Destination Out effect) did not use the blend effect anymore and some transparent glas objects were overall just strange, white glowing boxes. And I did not touch any of these objects. What's why I was looking for what I had done wrong for about two hours until I realized the only software that changed was Firefox browser, it updated. And since everything works fine in Chrome, you can be sure it's Firefox. Very annoying.
(And, also, people not using C2 are having problems with WebGL from what I get on Twitter.)