I've used this extension for several years, and it's been great most of the time. The problems that we have had are not the fault of the Youtube Video Downloader, but are the result of Google/YouTube changing their coding to prevent video downloaders from working! The developer of this one, Dishita, is currently working on the fix for the latest attempt by YouTube to prevent us from downloading their videos. Give him a little time to overcome this, then it should be working well, again!