GLContextWGL problem


Every time I close the firefox 4 beta with a page contains any webgl content. It’ll always pop up this message:

GLContextWGL: firefox.exe - Application Error
The instruction at “0x5ed195ec” referenced memory at “0x7ff30007”. The memory could not be “read”. Click on OK to terminate the program.

While this doesn’t really matter with the browser experience, but what is this error about, what had happened to my firefox?