I can confirm that - what you suggested to the other user above - I had to refresh (I did actually restart Firefox) to make it work.
So once it works its a BRILLIANT helper! Thanks loads. Next upgrade could also include a compressor/limiter and a de-hummer (for all this bad audio quality conference talks, you know)
Anyway: VERY GOOD JOB, mate!
Claus

edit: after testing for some weeks, I just donated you some bucks. Great work. Dont want to miss it. Keep it up! ;-)