It’s so simple to download flash video from YouTube or other site in a windows environment because much software available that can do it. but the problem occurred when we try to download flash video in ubuntu desktop I am personally research on this topic and I can't find any downloader that totally integration with Mozilla or any popular browsers so if you searching for a downloader that totally integrate with browser you wasting your time but I mention the best way to download video file to any, after reading this article you will be able to download flash video easily
You tube video downloader
YouTube downloader is a extension for Mozilla and available to Mozilla fire for add ones center just type it s and add it after adding this extension browse your favorite video and download or copy url of video download video with any ubuntu downloader if you want know more about ubuntu downloader click Best downloader for ubuntu you can also convert with the help of you tube video downloader
Minitube
Minitube is a YouTube desktop application.With it you can watch YouTube videos in a new way: you type a keyword, Minitube gives you an endless video stream.Minitube is not about cloning the original YouTube web interface, it aims to create a new TV-like experience. The program has a very easy-to-use and simple GUI (Graphical User Interface) that helps even the most amateur user. After downloading and installing minitube just video name and click search minitube show search in a left pane click for watch and then go video and download
You can download and install it by running this command
sudo add-apt-repository ppa:ferramroberto/minitube
sudo apt-get update
sudo apt-get install minitube