hi Jer, firefox will run plugins like flash in a separate sandboxed process and there are mechanisms to isolate content from different websites from each other. the firefox process itself doesn't run in a VM... not sure if this answers your question or you are looking for more details on the subject.

Thanks, is what I wanted to know. It seems a good idea to run FF in a VM so as far as it is concerned there is nothing else to wander off to and nose around. But it is what it is, thanks for your reply.

If you are using Firefox on a personal/home computer, you can use software like the following to help protect Windows from your browsers:

https://www.malwarebytes.org/antiexploit/ (free version)

It isn't a full sandbox or VM, so routine access to settings and folders is not inhibited, but they say it stops anything serious. I haven't tried it myself.

Are there any plans to sandbox Firefox as this seems to be a general security vulnerability of the browser. Chrome and Safari don't need to work in a VM environment yet provide it. By far, Firefox is my preferred browser but this does bother me....should I be?

yes, mozilla is working to transform firefox into a multi-process browser. https://wiki.mozilla.org/Electrolysis

My Webroot software has a Safestart Sandbox which I have never used, guess I am not actually that worried, but am interested as seems like a good idea. I do use NoScripts which gives some comfort.