First time I noticed it was yesterday. Trying to run Fx sandboxed from right-click menu or through Avast! UI, neither works. Firefox still runs, but no red border, no entry in UI/ProcessVirtualization for firefox.exe.
Have you tried clearing the sandbox of firefox and then running it again.
Yep, that was about the only thing I could think of to try and fix, tried it right away, no results.
Unfortunately that is all I can think of as I don’t have process virtualisation.
Yeah, I do have it, and that is all I could think of either. :-\ Apart from a re-install, anyway. Something I have managed to not have to do so far with Avast!, but maybe it is time to bite the bullet :
I’ll give it another 24 or so, then probably end up doing just that.
Wel, I can think of something, but that would be a big gamble. And I don’t want to take the risk to screw things up. So I emailed Petr about your problem, and what I would try 
Greetz, Red.
Ok, thanks, sounds like a plan. Part of why I thought to give it a day or 2 was it is Sunday, so they might not be around till tomorrow.
What about other application?
If you execute FF, is it listed in the GUI as running virtualized?
You can send me “snx_lconfig.xml” file (from avast data folder), I’d look at its structure…
Well, IE, for one example, runs fine sandboxed. I assume you mean browsers, but if you want me to run something else, let me know.
No, nothing at all is listed in GUI>>ProcessVirtualization when I run it sandboxed.
Sure, you will have them shortly.
Ok, figured something out. Non-virtualized Fx was/is hanging in task manager when I close it. And while it is still hung, if I try to run it sandboxed, it refuses and just re-opens regular Fx.
Would this explain it? i.e., was it ever possible to run 2 instances of Fx at once, one in sandbox, the other not? I cant recall ever trying, so I am unsure.
I don’t believe it was ever possibly to run two versions of firefox. I had that happen before with firefox still loaded in the task manager after I had closed it, I noticed that when I was trying to close down my system.
Whilst I can’t remember what add-on was responsible that was the problem, I don’t know how you can easily pin down what add-on it might be; try disabling the last one/s you installed, but don’t disable lots at one time as you don’t narrow it down enough.
This would fit, then. Just installed a couple of Themes last night before it started. Directly against the advice of a friend who says Fx themes are “buggy as an anthill” or something like that.
Time to “edit to solved”, I guess. Thanks for help, sorry for the goose chase.
You’re welcome.
Well I would wait a little while until I had caught my goose (found the misbehaving theme, etc.) before marking the topic resolved ;D