If your laptop has Bang and Olufsen speakers then it's likely that it's the audio drivers causing Firefox to freeze (dumb, I know). We had the same issue with a load of HP laptops at work. Basically, the only way to fix it for now is to prevent the process from starting by renaming the .exe . This thread explains it - https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fh30434.www3.hp.com%2Ft5%2F...