أضافة جامد اووى للمتصفح الشهيرFirefox وهى

Easy YouTube Video Downloader 1.1

شرح الاضافة هى تحميل من موقعYoutube
الفيديو بصيغات عديده وهى3gp,MP4,HD

Easiest Youtube video downloader ever, single click direct download buttons for 3GP, MP4 and HD qualities.

add buttons to download YouTube videos in 3GP, MP4 and HD quality.

If you receive html file while trying to download HD version as reported in comments, it simply means there is no HD version available for that particular video, Check this video to see how to test HD download functionality.

تحياتى
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