Hi, this seems to be a problem with Trusteer Rapport. Perhaps you could try updating or temporarily disabling it, to see if the crashes stop.

If your question is resolved by this or another answer, please take a minute to let us know. Thank you.

You're amazing! How did you know that!? Disabled it, and Firefox is working fine again! Genius!

Trusteer Rapport has been causing many problems of late.

Good call, Scribe

Davidrainbird - Thank you for your very enthusiastic response! It's always really nice to know when something has worked.

Thanks also to FredMcD for your comment.