kb2454826 crashes Firefox 4.0

[Quantum]

Does anyone else have this issue? kb2454826 was released yesterday and after installing it, FF 4.0 b9pre (64-bit) and FF 4.0 Beta 8 (32-bit) started crashing at start up. After uninstalling it everything works fine. FF 4.0 doesn't crash if I load it in safe mode.

EDIT: Running Windows 7 x64

 

[darktiger]

I think that is what is slowing down my FF 3.6.13