I've noticed recently that Firefox stopped playing YouTube videos and showing only black screen where supposed to be a video. So after a lot of research, many people clai… (閱讀更多)
I've noticed recently that Firefox stopped playing YouTube videos and showing only black screen where supposed to be a video. So after a lot of research, many people claimed that this is flash player problem. I tried to install earlier version but that didn't change anything. So I uninstalled Firefox and downloaded older, but stable version (34.0.5). And voila! YouTube shows videos again. After a week I noticed that YouTube again shows black screen box. Unintentionally, I opened Revo Uninstall and saw that there's TWO Firefoxes installed - one is that I personally installed and another is newest Firefox 37.0.2. So I uninstalled latest Firefox, but unfortunately it also uninstalled my older version Firefox. So this time I again installed older Firefox (34.0.5) and made that it never look for updates and won't install them. YouTube started to play well. After a few days, again Youtube doesn't show videos, only sound plays, and you can see actual video frames by pointing cursor on video time line. So I checked installed applications and AGAIN found mysteriously installed latest Firefox with the old one. So can anybody help me to stop latest Firefox automatic installation and only leave the old one? Any solution would be very appreciated.