Super convenient extension. It lets you open or save the cover art of any YouTube video in top quality with just a couple of clicks. It's fast, and the interface isn't bloated. If you often need thumbnails, it's an absolute must-have. Highly recommended!

Легко можно скачать обложку видео

This works super well. Glad I found this one, because it's not intrusive, just a little button in the nav bar, and works to view AND download thumbnails (just right-click and save the image from the preview) – perfectly fine!

Very simple, just adds a button at the end of your address bar that shows the thumbnail once clicked.

Best Add-on of it's kind!

It's button is only shown on supported websites. So you don't waste space on the firefox UI.

Developer reacts to feature suggestions on github. 👍

So good and easy to use. Hope to have more choice of quality.