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It doesn't seem to work on my mac, it works on my pc though...

edit: the method to download mp4 files doesnt work i mean

It works fine on my Mac. Not sure why it wouldn't for you. If dragging the "Get YouTube video" link to your bookmarks bar doesn't work:

  1. Create a bookmark with the following as the address:
    Code:
    javascript:if(document.location.href.match(/http:\/\/[a-zA-Z\.]*youtube\.com\/watch/)){document.location.href='http://www.youtube.com/get_video?fmt='+(isHDAvailable?'22':'18')+'&video_id='+swfArgs['video_id']+'&t='+swfArgs['t']}
  2. Go to YouTube and view a video
  3. While viewing the video, click on the bookmark you created

I'm using Safari.
 
ok well go back to the website and where it says get youtube video in the white box. click and drag that white box to your tool bar (i assume you are using firefox since its the best but im sure safari has it too). it should go on right under your url address bar. then go to the video you want and click the button in your tool bar and it should download it.
 
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