YouTube is a mess... People telling it's fault of this extension doesn't know the real truth. Try downloading anything from YouTube with different tools and you may find most of them doesn't work, too. Instead of publishing harassment arguments against their developers, think twice before saying anything.

Haven't you read the latest warning from Easy YouTube Video Downloader website from their support section? Read it again:

" I'm aware that the web extension is producing 0-byte downloads or files that won't open. This is because YouTube has again changed codes that breaks downloads.

I've worked around the new restrictions and fixed the issue caused by YouTube's latest code changes. Version 24 (v24) has been submitted to Mozilla for approval. Until then, please use the temporary fix below to get downloads working again.

Get the temporary fix from here: (see it at their official site)"