This is a step-by-step guide for getting DownloadHelper on your browser. The main page about this and it's is can be found here.
A short description about DownloadHelper: It's a add-on, with which you can download videos, audios and also pictures in a bulk from ANY website in the world with just ONE click. In order to use it, you don't even have to install it on your computer's hard-disk.
In addition to that, as amazing as it might sound, you can "Download & Convert" a video or audio to any format of your choice and also share it on your social network directly.
Here a step-by-step guide on how to add DownloadHelper to your browser:
Click the "ADD TO FIREFOX" button on the page. Next you'll see something like this on the top-left side of your browser.
Click "ALLOW" on the popup.
Wait for a few seconds.
Click "INSTALL NOW"
You'll see a popup on the top-left side of your browser that says "DownloadHelper will be installed after you restart Firefox"
This is it. Just click "RESTART NOW"
Now the next time you start surfing on the website, you'll see the DOWNLOADHELPER ICON on your browser. Click it to download any video, audio or picture on any website.
To know more about what DownloadHelper is and how you can download any video, audio or picture gallerias with its help, go here.