Very glad to see that Iridium is back!
I tried Nova Youtube, Enhancer for Youtube and Improve Youtube but I am staying with Iridium.

Actually works with the new layout, and the theater mode with full viewport video and sliding top bar is the best implementation so far. Glad you're back.

Small recommendation: Option to hide the scroll bar, so the video can actually use full width. Or even make it pop-in on top.

Not sure what happened 3 years ago that this kept getting 1 star ratings, I installed this 2 days ago and it's done everything I wanted and more, fantastic. Will update my review later if I run into problems.

Can the Scroll volume function provide an option to hold the Shift key or not? Edit: Thanks for the option.

Please restore the previous version 2.0.6, this 2.0.7broke several features.

Edit: autoplay is now a button...

Great extension, an absolute must-have, unfortunately Mozilla has recently decided to be extremely anal about it, so it's no longer supported here. Go to the developers github for newer versions

IMPORTANT: Use old version!
This is a great extension with many useful features. There aren't any alternatives offering the same quality. Amazing work!
HOWEVER, due to some issues explained on the GitHub page, most of the functions are gone in the current version. Until the functionality is restored, you should use the latest "old" version for now, which is 0.2.5. You can find the version archive under the "More information" section of the store page.

It does everything it advertises and blends in so well with youtubes UI. I can't wait till they add more features.

Thank you Particle for being amazing. I've been using Iridium for so long. I hope that my favorite feature, reversing playlists, comes back someday soon.

I don't have a stable income yet, but once I do I'll support Iridium. Thank you so very much for the amazing Add-on.

Works flawless. Although not all features from the older versions are implemented, those which are implemented work flawless, as expected from the author who does an amazing job. I'm looking forward to future development.
Too bad most people give the rewritten version of this addon a negative feedback, but the fact that he now uses a Firefox API to more reliably inject changes to YouTube video player is a very good development. This strengthens this addon and will lead to a much better user experience in the end. Remember when similar addons which claim to disable autoplay actually only pause the video after the page was loaded and if you were unlucky the video was played for first couple of second anyway? (until page loading was finished) This will not happen with this improved injection method. It is really great. I enjoy this so much to never have to worry about any videos starting without my permission. Furthermore this will strengthen Firefox as a browser because this new API is only available in Firefox, not in Chrome.
I'm greatly impressed that the author had the courage to overthrow all legacy code and start a new version of his addon with improved techniques. This is something a lot of developers are afraid to do, and therefore their software dies in complexity.
I cannot understand why people complain because the old addon was broken anyway by recent YouTube changes. So there was nothing to loose.

Going back to previous version... Lets just say that the next time I'll update is "coming soon"

I went back to "Version 0.2.5" and everything works as it should ;)