I use Free Download Manager. The problem is, sometimes I try downloading files from file sharing websites and they often feature javascript or redirects that don't let me get the url for the file I want to download. When I start a download (with normal Firefox popup window), I can copy the file URL and try pasting it to FDM, but the websites usually don't let me start downloading the same file more than once from one URL.
Is there some plugin for Firefox or Chrome that lets me get the proper file URL without starting the download?