I have just installed this again (realised after I installed it that I had used it years ago in FF1 days but never really found it useful after having it sat there for ages) and have uninstalled it for 2 reasons.
Firstly it doesn't do what I want it to It tries to play SWF streams from Youtube rather than the embedded video which is no good to me.
Secondly, upon checking the players that it had discovered during installation it had picked players from another installation on the same computer. It shouldn't be looking in other installations. Basic error that should have been done properly from day 1. This addon is too old to be so shoddy. This is the main reason I have given it the single star, only because I can;t give it none.