There are many things that you can drag and drop in Firefox:
1. Drag the favicon of any site to your home icon to set it as
the home page.
2. Drag a hyperlink (or image) to the new tab icon to open the
link in a new tab.
3. Drag a download link (or image file) to the download icon to
instantly download the file.
4. Drag a highlighted word to the search bar (beside the address
bar) will bring you to the Google search result page for that
word. If you drag the highlighted word to the address bar
(and press enter), Firefox will perform a Google 'I'm Feeling
Lucky' search
