Rated 5 out of 5 stars

it is AMAZING!!!!!!!!

but so bad it doesn't donwload the ORIGINAL mp4 anymore :(

This review is for a previous version of the add-on ( 

Not sure what you mean, CYS can download "Fmt 138 MP4 Original 2304p" and "Fmt 272 WebM Original 2304p" (DASH formats). Please contact us at the support email if you need more info. Thanks for the five stars!!!

Rated 5 out of 5 stars

Hi everybody this app does work as intended, please follow the developers instructions as provided on top of this page.

Apparently firefox moderators have stopped the apps latest version for commercial reason, which is pretty sad. Firefox should be more supportive of their addon developers. More than stealing we see this method as a way to save our bandwidth when watching a UHD video multiple times.

Anyway as far is the app is concerned, works pretty well.

Kudos to the developer.

This review is for a previous version of the add-on ( 

Thanks for the support!!

We have uploaded a new version (v5.6.3), hopefully this one will pass review. You can download it here:


Icon doesn't work Rated 2 out of 5 stars

Clicking on the icon in the toolbar doesn't do anything.

For info, i have already unhided the Console Window in Options> General tab but still nothing happens when clicking on the icon.

I am on windows XP SP3.

This review is for a previous version of the add-on ( 

Posting bugs in the review section does not help; we need more information. Please create a new issue at https://cys.mantishub.com or contact us at our support email (cytsaver@hotmail.com) with this information:

-Firefox, FFmpeg and CYS version you are using. Does this happen on all videos or just some? If only some, please provide us with some links, thanks.

CYS 5.5.3 Rated 5 out of 5 stars

Version 5.5.3 was removed from site. I maked a copy of the add-on.
For Windows x64. Just decompress and put into C:\Users\youruser\AppData\Roaming\Mozilla\Firefox\Profiles\????.default\extensions



This review is for a previous version of the add-on ( 

Version 5.5.3 can be found here:


A new version should be ready soon...thanks for the 5 stars!

Best WORKING YouTube download tool; needs version 5.5.3 and FFMPEG Rated 5 out of 5 stars

Folks, this is the only WORKING app that lets you download full 1080P from YouTube WITHOUT UPCONVERTING FROM 720P. You NEED FFMPEG in order for it to work, and you should also configure the plugin to NOT HIDE the FFMPEG window. Do that and it WILL WORK.


You NEED version 5.5.3 or it will NOT WORK.

In a very sad turn of events, Mozilla, going against its users, has removed version 5.5.3 from their site. I in fact had a Mozilla moderator tell me that he believes that addons like this should be completely banned as he views that this addon is only used for "stealing." Wrap your head around that for a moment. This is also not the first time that Mozilla has removed working versions of Complete YouTube saver from their site with no explanation.

Sadly, it seems there is no Internet link to download version 5.5.3 anywhere else on the net as the developer does not want to set up a GitHub for some reason which would be the best way to solve this problem.

I recommend that you visit the developer's site, and send an e-mail to the e-mail address posted on their front page and request version 5.5.3 from them.

Hopefully something will be figured out soon to support the users of this very useful addon.

This review is for a previous version of the add-on (  This user has a previous review of this add-on.

Thanks for your review, we appreciate the support!! Yes, v5.5.3 was reviewed and removed by an editor. A new version should be up sometime this week. For now, you can download v5.5.3 here:


WORST APP EVER!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Rated 1 out of 5 stars

still not working par TWO
ONE STAR or LESS due to incompetence of developer(s)

This review is for a previous version of the add-on (  This user has a previous review of this add-on.

Rated 4 out of 5 stars

This add-on had worked for me before and I loved it because it was the only one that allowed me to download 480p quality, which is often the highest available.

Recently, 5.5.1 stopped working and I updated to 5.5.3, which appeared to be working fine at first glance. But actually it wasn't. I encounter the following problem: When downloading 480p movies, two temporary files are created, which are supposed to be merged to one mp4 file after the download completes. This conversion fails, the two temporary files get deleted, and I am left with nothing.

I am on a Mac. I have downloaded the FFmpeg linked at the CompleteYouTubeSaver website, so should have the most recent version that is expected to work well. I have located the folder containing the FFmpeg file through the Options dialogue, and this looks alright to me, as the appearance of the dialogue changed in the expected way.

Any idea what I am doing wrong? How can I find out what may cause my problem?

This review is for a previous version of the add-on ( 

You are not doing anything wrong, a fix is in the works for Mac and Linux problems and should be ready very soon. Please bare with us. Thanks for your review.

Rated 2 out of 5 stars

0 byte issue again with version 5.5.3....

This review is for a previous version of the add-on (  This user has a previous review of this add-on.

Mac and Linux users, if you are still having problems a fix is in the works

Rated 4 out of 5 stars

By far the best YT video saver I've ever used. Tends to work when most others don't, and the use of FFmpeg to allow such a variety of A/V combinations (as well as audio or video online) is sheer brilliance. Hopefully the only YT downloader I'll have have to use again.

My one criticism (for which I sadly detracted a star) is about the distribution and update process. When the program doesn't work (usually due to new YT coding that needs to be compensated for), there's no error message....just a small spinning box, then the menu that appears as normal, and then downloads 0 byte files without indicating why, or even that an error has occurred. Very frustrating interface issue.

What's more frustrating is how these are addressed. Sometimes it takes a week or two for a message to appear on the addon page, saying that YT code changes have necessitated reprogramming. Again, this should be an error message in the web browser itself, when the error occurrs, not something we might happen to see in a week or two.

In my opinion, this plugin badly needs a Github page. That way we could go there and tell instantly what the problem was, what was being done about it, when it might be fixed, etc. Would also make it easier to contact the developers.

Another idea would be to implement a secondary install stream, like Mozilla Archive format's "experimental" stream. I don't really care what the Mozilla add-on reviewers think of the plugins I use! I would love to be able to install directly from Github or the current development page.

This review is for a previous version of the add-on ( 

Thanks for your constructive review! Secondary install stream and Github page...in the works as we speak :)

revision 5.5.2 removed Rated 4 out of 5 stars

Revision 5.5.2 removed by Firefox,why is that?

This review is for a previous version of the add-on ( 

Yes, v5.5.2 was reviewed by an editor and disabled. Just a technicality though, they are requesting some more info. Should be up again shortly, please bare with us, thanks.

Fabulous Rated 5 out of 5 stars

Oh God! This a fabulous add-on. Has been tested on Win7x64 SP1 with FFMPEG64 and worked like a charm. the "muxing" is working with no any single issue. Thanks a lot for the developer. For guys who're complaining, please download a good copy of FFMPEG at http://ffmpeg.zeranoe.com/builds/ and in case in the future, the add-on starts to download 0 sized videos, that's mean the Youtube has changed something, so do not come here to complain about the add-on. it is enough for the dev. keeping himself up to date with such changes.

This review is for a previous version of the add-on ( 

We appreciate the support!!! Thank you!!!

Very good and very bad points Rated 2 out of 5 stars

The good: It can download all DASH formats! Very useful. A convenient button is provided.

The bad: It requires ffmpeg to even recognize audio at all, instead of showing raw streams. Once you configure ffmpeg, you have to restart the browser, but it doesn't tell you that. Once you configure ffmpeg, there's no way to download bare DASH video streams, you have to let it mux in audio. It forces either H264/AAC or WEBM/Vorbis on you, but the best WEBM/AAC is always the absolute top quality available. The button is impossible to move, it's permanently welded to the left of the address bar, instead of being able to move it to the main menu or elsewhere, and it's always there on non-YouTube sites. No right click options.

Enough problems that despite the fact that it works, unlike many plugins, I'll probably uninstall it and look for an alternative.

This review is for a previous version of the add-on ( 

fantastic team support Rated 5 out of 5 stars

Had a problem with a url with download size 0...write to support...and they answer immediately!..what I can say?
marvellous plug in...and an amazing developper team...thanks again guys!

This review is for a previous version of the add-on ( 

Glad we could be of help! Thanks for the review!

0 bytes Rated 2 out of 5 stars

Version 5.5.1 ... Was doing great at first... then all of a sudden files become 0 bytes.

This review is for a previous version of the add-on ( 

Rated 4 out of 5 stars

CYS worked in the past fine for me, also now seems to do the job. So far so excellent!
However: now on a new system I find no longer an option to save my settings; the selection of formats I make gets ignored completely and the preferences window has only a "close" button, no "save" to be found. FFMPEG path is remembered and and also the columns. They do not fit into the detailed menu, though.
So at the moment the usability has (minor?) glitches, but the functionality seems to be complete.
Therefore only 4 stars for a 5 star addon.

System: FF 30.0 CYS 5.3.0 under SolydK, system up-to-date
(and yes, I restarted FF several times...)

This review is for a previous version of the add-on ( 

Thanks for your review. We've had no problem in CentOS. This sounds like it may be a possible corruption, please install CYS into a new, empty profile and let us know if it solves your problem (cytsaver@hotmail.com), thanks.

Rated 4 out of 5 stars

Please add playlist download

This review is for a previous version of the add-on ( 

CYS has all the capabilities to also add bulk-downloading functionality (DASH included). Look out for it in a future update, thanks.

Rated 5 out of 5 stars

Works PERFECTLY. Not just plug and play but very easily set-up. Since it is able to save the DASH formats I have given this addon the full five stars. I was using other youtube savers beforehand yet 1080p was always unavailable so I am thankful and have respect for the programmer(s). I am using v5.3.0 and always the newest Firefox.

This review is for a previous version of the add-on ( 

Much appreciated, thank you. Please try the interim fix (v5.3.0) here:


Rated 5 out of 5 stars

Works perfectly. Pointed the add-on to where my ffmpeg.exe was, added the add-on button to my toolbar and restarted Firefox.
No problems downloading 1080p / high quality audio. No problems with ffmpeg combining the audio + video files (except for the known issue of needing to say 'yes' to overwrite existing file in this version).

This review is for a previous version of the add-on ( 

Thanks for your review...an update should be ready later today.

Works Great Rated 5 out of 5 stars

This add-on performs as advertised.
Thank you for creating it.

This review is for a previous version of the add-on ( 

Rated 1 out of 5 stars

Forget it. It doesn't work. The icon doesn't show when starting any Youtube video. Have installed FFmpeg correctly and using Windows 7 and FF 29.0.1

This review is for a previous version of the add-on ( 

The program does work, you could just click on the "Customize" button in Firefox to drag the CYS icon back to your toolbar. Your "review" is actually a bug report, however, in this section, such posts are unwelcome, as described above - our support email address is meant for reporting bugs.

We are proud of our work, and frankly, we feel your 1-star rating is entirely unfair and uncalled for. Will you, please, write a proper review in stead? Thanks