Rated 1 out of 5 stars

per DonChino el feb. 2, 2017 ·

I am on Firefox 51+ 32-bit and this did nothing to stop the videos on YouTube, so I had to uninstall. Remember, you have to uninstall and remove Adobe Flash from your computer or at least from Firefox. I switched to the add-on - HTML5 Video Everywhere! - and it finally stopped autoplay of HTML5 videos. The only "bug" is on CNN.com which requires two clicks to play, but the only one I found that worked stopping autoplay.