Simply the best.....waiting for new version.....


Realy loved this module it was the best.
Hope the devs didn't abandoned the project for the new version of Firefox !

In the meantime i can suggest you an app on android for downloading youtube audio and vidéos called NewPipe (you will need F-droid store to find it)
Happy downloading guys


what is the progress?



Used it for years. For me it was the best Youtube downloader, with lots of great options and very simple to use, just couple of clicks. I miss it very much since Firefox Quantum update. I tried many other downloaders but none of them was that complete and hassle free as C.Y.S.




This was the only free (not freemium) and complete (all resolutions) downloader for Youtube but:
- on Firefox 52 ESR, the latest 2 versions stopped working (unclickable menu).
- lately, v5.7.31 causes some heavy memory leak on Youtube that hangs the browser.
- the dev wanted to completely rewrite the addon as a webextension, but there are no news since months. And the email address seems deactivated. This extension has probably been abandoned. :(



This WAS truly the best youtube downloader I ever used until it updated itself a few days ago, causing it to no longer work.

The SOLUTION (that works for now, anyways):
Download and install Version 5 . 7 . 31 or older and TURN OFF AUTOMATIC UPDATES.

Hope this helps someone.

By the way, Complete Youtube Saver obviously doesn't work with Firefox Quantum (yet), but it DOES STILL WORK with Pale Moon. A lot of the other popular Firefox Add-Ons work with Pale Moon, too.


I was able to make use of YouTube with this extension until just recently when it suddnely stopped working and I really need to be able to view donwloaded videos offline as some places in my house get no internet commections and one is the best for watching videos.
I'm also stuck using Firefox v39 as later versions just didn't work or at best were highly unstable on Windows 7.


This was simply the best and easiest direct downloader for YouTube, thanks to the pop up menu showing all available formats.

Regarding slow speed, this is coming server side from YouTube... ANY utility will have the same speed restrictions. Looks like they are throttling their bandwidth so nothing plays faster than it would for streaming... understandable; the amount of bandwidth they use must be staggering.

Sadly, it looks like this legacy add-on finally stopped working all together recently, as it will no longer download anything. The pop-up window showing all available formats is still working and useful however.

I would encourage the author to come back... web extensions isn't really needed as there are several XUL forks of Firefox now that people are using that this add-on in its current form can still work on... Pale Moon, Basilisk, and Waterfox, for example.



The big advantage of this addon (so far) is it is the only 1 that I've found that can automatically reassemble 'DASH' formats that R split into many files on U-Boob, but currently not working @ all. Found a couple other addons that do work... though no 'DASH' support, so not all the file versions R made available 4 downloading but DOES work more reliably than even most downloading sites, which have trouble with pages like this long video. What I am getting at is maybe some of the features of THESE programs that DO still work can be transferred into 'CYS' 2 make IT work AGAIN =)

Pete Thorn Sunday Live #18 (tried 5 different 'downloading sites' & all failed!)
But CAN download with these...

Video DownloadHelper by mig
Works OK sometimes & sometimes not = tends 2 require special configuration where U WA$TE download bandwidth attempting 2 play the video so it can get a link (badly written addon).

Youtube Best Video Downloader 2 - MP3 MP4 1080P by YouTube Best Video Downloader 2
NOTE: I have since discovered this second item (YBVD2) thing is either broken or a virus-like $cam, as it causes CPU-hogging nonsense even sometimes when not attempting 2 download things on Youtube. Maybe it is seraching tabs for login details 2 rob U or something, who kows... removing the addon stopped the problem. Will try ALL of them soon 2 C which others provide at least some of the functionality that CYS USED 2 have (back when it worked at all =)

Problem with 2'nd 1 there is have 2 actually start the video playing 2 get file information, which still omits dash formats... but at least it is not a $CAM like most of the totally non-functional bull$hit $PAM 'addons' on this web site =))

Partial Fix Idea =) Seems when trying 2 download some videos, like 'Q&A' stuff that is over an hour long, even on downloader sites it fails. I'm guessing U-Boob is seeing if it is pulling the various multiple ad interruptions or not then cancels the transfer if no ad is played, so a way around this is 2 ALSO download N E ads that R prompted & then discard them when things R complete. That way it looks as if it is a browser playing them back 2 a human so they can't tell the difference =D U would of course not play them, because that WA$TE$ CPU, but make it seem as such, by having the appropriate 'user agent tags' & whatnot, then collect the 'buffers' 2 assemble the video as a single file as usual. Again, B sure your addon works with Firefox 52 ESR (last XP version) on back, otherwise it's useless 2 about 30% of the market. There is NO reason 2 keep chasing a CRIPPLEWARE target that ditches your preferred programming language. People can use a portable firefox 52 version on N E Windoze machine XP & beyond. Note this 'pull the ads' feature could B a workaround 4 N E other video crippling U-boob ever does. If it can't tell U from a browser watching it (pulling just as flash or whatever does), there is no way they can block it or will even try 2. IF U R NOT GOING 2 SUPPORT FF 52 THEN OFFER YOUR ITEM AS A STAND ALONE PROGRAM THAT CAN WORK ON WINDOWS XP! (& beyond, as XP stuff typically runs fine on later OSes).

Note: Your whole perspective on the compatibility issue is in error. It is not your add on that is incompatible with Firefox. It is Firefox that has stopped supporting the features we want. It's like with Windows XP. About 30% of PCs still use it, because we need it for actual work. there are a bazillion versions of firefox that work, including 52, which is available as a portable & runs your add on on XP. There is no need to ever modify your code to accomodate a moving target fail train of unnecessary crippleware nonsense. Refine it for 52 backward, because various modern operating systems can run that AND so can XP. This statement is a mistake: "With the release of Quantum, CYS is no longer compatible with Firefox. We are still working on the new version. There are limitations to WebExtensions that we are trying to work around." Don't bother. Make it work with 52 (& rearward) or it is useless to us 'power users'. Stop by any bank for instance and look at their machines. Just an example. Portables of tons of versions R available here & elsewhere:

UPDATE: Don't bother trying version 5.7.31. Although it works on some videos, it often does not, & even causes an 'endless feedback loop' blinking like crazy & eating CPU like mad until the add on is disabled. Seems like Youtube looked at the code and tasked some programmers with writing something 2 mess it up. The key is 2 making your add on appear indistinguishable from a web browser on Youtube's side =) How can it ever save with the wrong name when it's written right there on the page? You should approach your coding differently. It should pull all the items 'through' the browser, including the name for the file, the links to the video & sound bits, etc. Then it will ALWAYS work yes? Time is not an issue. We can just leave the browser on & have projects (like to download a playlist) over night, or multiple days, or in sections (with resume funciton) so can spread it out over days or weeks.

For now, if you want 2 B sure 2 get the videos, try downloader sites like:
http://videater.com/ <-- Most flexible & reliable. Some U-Boob vids others fail on this can get! =)

Main points:

1) To address 'time' requirements of keeping things working and improving the program, you could maybe start a 'patreon' or some other type of funding / donation mechanism 2 help people easily contribute $$$ 2 CREATE the 'time' 2 get things even MORE awesome =8^D U could also of course SUBCONTRACT the troubleshooting & improvements by simply paying them when they verifiably complete the work, rather than up front. In other words, U hire programmer(s) 2 solve specific issues & they R ONLY paid IF they manage 2 fix it, etc. This way U do not WA$TE $$$ (or time on them). N E programmer who is unwilling 2 do this is just trying 2 $cam U N E way, so move on =)) If they think it will B 2 hard, U can always negotiate the price 4 different fixes & shop around, but NEVER pay them ANYTHING up front. If they R worried about not getting paid, U can offer 'escrow' 2 hold the work contract funds 4 them via 3'rd party 2 verify solid, reliable completion of the work so THEY can't get $cammed either. EVERYBODY WINS! =D

2) Youtube downloading via CYS is (currently) broken. A fully functional version of CYS that can download videos from Youtube and will run on Firefox browser version 52 (or earlier / lower numbers) should always be available, because that is the last Firefox version that supports XP, & Windows XP has about 30% of the total PC market world wide and is never going away. They never stopped supporting it, and it is run by tons of businesses, etc. They just claim otherwise because they are trying to $cam people into WA$TING $$$ on 'latest greatest' stuff that is often far WORSE than XP. ALL of my suggestions below concern the Firefox 52 compatible version.

Example: I will never run any versions past Firefox 52 unless they make them support XP. There is so much XP can do that other OSes can't, I won't be switching, & the same goes for endless millions of businesses & other 'power users' world wide. Some people are 'casual trendies' into the 'fashion statement' of having something 'new', even if it is much WORSE in quality & function, whereas many others care mainly about PERFORMANCE and FLEXIBILITY for performing actual work =) People who want the 'latest greatest' Firefox version can still run other older versions via 'portableapps.com' (& vice versa) & other available 'modular' designs. I currently have about 25 different portable web browsers on my PC which I use in different configurations for different things including checking web site design incompatibilities (so things are arranged the right way no matter who is looking, etc.), everything from Safari (yes, on Windows), to Chrome (bloatware) & others. Us 'power users' are no stranger to running & using multiple versions of firefox SIMULTANEOUSLY & simply by configuring the terms in the 'FirefoxPortable.ini' file to read as follows:

3) CYS should automatically retry when fails (and pull video names from the Youtube page itself so always correct name ~ otherwise often has name of video from another tab! =P)

4) CYS should add 'channel downloading' type 'spider' functionality, combined with 'resolution & format preference rank' user configuration options. More detail on this IMPORTANT concept below...

5) The 'User Format Preference Rank' options should also be savable by the user as 'custom presets' for recall of various 'templates' for project types the user could name themselves (such as 'OOG sound files only' vs '1080p/720p' music performances, vs. 'smallest 3gp' for 'talking head vlog trash', etc. More details below ~;)

6) Add 'AV1' (Aye Vee ONE, not 'AVI / Aye Vee Eye) support when available. I've heard that U-Boob will B adding 'AV1' format videos as the next generation codec after VP9 =)


Do not bother trying 2 constantly change the language of this addon to work with newer versions of Firefox. There are plenty of portable firefox fersions (like on 'portableapps.com') that will run the 'old' style language, so changing the interface language is totally pointless. They R all relatively small, super efficient (compared 2 bloatware like Chrome 4 instance) & E Z 4 running TONS of cool 'legacy' add ons =D I use XP 4 all my gear because it is the most flexible. There is no need 2 change, because newer does not necessarily mean better, & instead is often much WORSE! U might also consider making this a stand alone application like 'J Downloader' & others =) PEOPLE WOULD HAPPILY PAY FOR A TOOL WITH THE FEATURES OUTLINED BELOW THAT CAN DO FULL CHANNEL DOWNLOADING.

Also, do not stop development of product(s) that will run on XP! Future OSes will ALSO run the XP versions of Firefox, & XP still has & will continue 2 have more than 30% of the PC market worldwide. Businesses all over use it, etc. Last version of Firefox that supports XP is 52, so if U only update the plugin for Firefox versions AFTER 52 then it will remain BROKEN & NON FUNCTIONAL for all the rest of us who can NOT run things past 52. Please stop pretending U 'have 2' change everything just 'because' some random change on the 'latest greatest' (not really) Firefox program THAT NOBODY IN THE WORLD NEEDS TO USE! They can run Firefox version 52 9or earlier) & it works great! =D In fact 4 most sites the fastest browser by far is the 'ancient' Opera 12 = the last Windows '98 version. U have never had real browsing speed (with proper graphics) until U have tried that gem =) It's literally about 5X faster 4 most pages than the fastest versions of Firefox.


I notice Youtube downloading is much slower than it used to be. Are they throttling them? You know, to make room for all those vital 4k 60FPS talking head bull$hit non-videos clogging their bandwidth? HAHAHA Oh yes, we really need 60FPS HD for some 'here's my daily schedule' vlog garbage =)) Youtube loves 2 WASTE bandwidth on that junk instead of give us speed where needed (on REAL videos, like music performances) = insane. I also notice lately your Complete Youtube Saver plugin won't work all. When clicking a resolution in CYS it does nothing, with only a 'save as' type dialog pop up, and still won't download if click that, etc. Maybe they have changed the language for video data links. Please fix this (and be sure it can run on Firefox 52 or earlier =)


Ideally when downloading videos & audio or whatever from them your plugin should mimic the web browser so Youtube thinks U R a browser when downloading the video parts =) Maybe pare it with a 'user agent string modifier' in there? This video 4 instance plays fine and will download via various 'downloading sites' but does not download in any of the multiple versions of Firefox I tried it with using 'CYS' lately.

It would B GR8 if U had an option 2 ignore all the video content & just download all the OGG sound files (for music playlists), & also an option with 'download type priority' list, so we can rank the preferred formats 2 download from a channel (automatically), like rank 1080HD (in smallest file size version) Webm highest, followed by 3GP smallest, or whatever order (with little box next 2 each format in a the configuration settings someplace so tries the next available format in order of user preference when the 'best' in rank is NOT available). IMPORTANT: Within a given resolution & file type, it is best 2 select the smaller one, as for instance both VP8 & VP9 videos show as 'webm', but the SMALLER of the 2 in a given frame size is the VP9 one which is preferable because it is ALSO the better looking one (more efficient codec). This should B up 2 the user of course. This maybe should B noted Y the 2 R different sizes =) Also of course a 'channel' & 'playlist' downloading function should B added so users can spider 4 videos (with format preferences as noted) without having 2 do it all by hand. Here would B a good example:

Download Channel (via page links):
1) User pastes in page of linked videos. Example...
2) User selects 'project properties' & selects their favorite 'format preference order' from the available configurations they saved, such as (example):
1'st = OOG
2'nd = AAC (in other words, if OOG is NOT available, download it in AAC, etc.)

For downloading 'motion' music videos it might B slightly more complex (according to user definitions, so if 'rank 1' fails, like it is not available, it moves to 'rank 2', & so on down the line until it can find something 2 DL.):
1'st = Webm 1080p (if available)
2'nd = Webm 720p ...
2'nd = Webm 640x360, in smaller file size ( VP9 = more efficient codec)
3'rd = Webm 640x360, in larger file size (VP8 = worse codec)
4'th = 3gp 176x144, etc...
NOTE: The DEFAULT for downloading videos should B Webm with OOG audio format. It sounds better than AAC, & Opus is absolute GARBAGE.


When downloading multiple videos in a channel copying task it should spread them out so does not seem like a spider, like doing them one at a time and with a random minute or so in between, and we can just run it overnight, etc. That way they won't block the user's IP, etc.. Very importantly though again, a way to NOT download all the video parts but just the audio 'OOG' files would B GR8 =) OOG sounds better than MP4 (AAC), which is better than Opus (which is absolute krap, 'kuz forces uneven resampling 2 48Khz = harshness). AAC is also harsh, but not as bad as Opus, because AAC deletes highs & then 'synthesizes' them by guessing = disconnected feel, like a bad 'boom sizzle' speaker with a metal tweeter = jaggy edgy fakeness 2 it. OOG is natural sounding =D If U don't believe this stuff, go download some 'Rammstein' music videos & compare the texture of the guitars. Notice the AAC is harsher, & the Opus even worse than AAC, but the OOG sounds chunky & massive = more realistic concert style =) Vocals R also more smooth & natural. Would B kewl 2 B able 2 'mux' (combine) OOG into N E other video format also... like say, MP4 (for compatibility with certain TVs & players) combined with OOG sound (4 more naturalness than AAC =)

Another bug with the program is it very rarely works the first time you try to download something, so it may as well AUTOMATICALLY RETRY if it gives a 'failed' response within the program. It should also give a 'report' with links to all the videos it was not able 2 download, that can B hand copied by the user using a 'copy' right click command with their mouse, or something similar, so they can go manually try & download those (via 'downloader sites' or whatever, if they can't get CYS working on those pages). 4 more ideas & tips contact me at 'balkanguy at live dot com' =) Overal, the idea is 2 B able 2 download music video & other Youtube channels in a user configurable way for 'offline browsing' =D Personally I never even play Youtube videos except offline, because I run them through FFDShow & AC3Filter using MPC-HC to denoise & 'upsample' things so looks way better than via a web browser =D 2 bad your addon stopped working! =(

Other Ideas:

Lastly, this would be sort of a 'convenience' feature for quickly improving audio quality, is offer the option to re-encode the OOG stream (or AAC audio if OOG not available) into high bit rate MP3 (like 256Kbps 'CBR' Constant Bit Rate) to drastically improve the sound, & then (option to) 'mux' (mix) that in to the video to replace the original audio. It has the effect of making it more lush & 3D sounding, like upsampling a photograph digitally 'interpolates' between the pixels, UPsampling audio has a similar 'smoothing' effect for better sound (at the price of larger file size). Some people would love this feature, especially for music videos, & since Youtube stopped offering high resolution audio on ANY of their 'content'. It's not an ideal solution (would be better if Youtube did everything in 256Kbps MP3, because it sounds better than ALL other compressed formats, including Opus), but it's 'somewhere between' and certainly better than what is available now =D Would also be nice if players like MPC-HC offered 'on the fly' UPsampling this way for ANY sound content, but that is outside the scope of your plugin I guess (different program). You might contact them with the idea though & C if U can convince them =D Hopefully they will add 'AV1' support too.

NOTE: MPC-HC for a while did not support Windows XP. However, being a power user able 2 explain the advantages, they RETURNED XP support to it. This is great because VLC is slower and infinitely less flexible & was the only 'quick & easy' VP9-capable XP player with relatively low CPU usage, but still a hog compared 2 MPC! Whatever U write should always B able 2 run on XP. If there is some new 'development tool' that tries 2 pretend U do not need 2 support it, or purposely removes that functionality as if it is 'no longer needed', don't believe it. It is just a $CAM 2 play into the 'keep-buying new even more broken $hit than the old broken $hit'. It is an imperfect world & no OS is error free, but XP is still the best. Every year I try out the competition, from Linux & they rest, & they're all still far behind in flexibility, etc. That's Y tons of real bu$ine$$e$ $till u$e it =)


Very useful and professional program.
I hope it will be get back soon for Firefox Quantum.




For some time ago , very slow download dash audio formats (opus) !!!


Besides the command-line youtube-dl, this is by far the best download utility for youtube videos. It tells you exactly what type of video and audio you are downloading, lets you merge them for DASH formats, download subs....basically everything one could want. Youtube-dl gives slightly more control over allowing one to mix disparate video and audio types, which is extremely intelligent, but in all honesty the "best" video this addon can download is the best one that I want 99% of the time. I can't wait until they release a version for WebUtilities, but until then I'm maintaining a version of FF Portable with FFMPEG installed so I can use this when I want to download some videos (and don't want the headache of diagramming out the YT quality flowchart and entering the subsequent codes in youtube-dl.

I still support you on Patreon (though I don't think it takes my money). I hope you all keep working, and remember that with the quality you had before (and maybe a few tiny hints from yt-dl) many denizens of the internet would be glad to pay. Thanks so much for your work over the years!


OK, sorry nobody thus far is able to make an add-on out of youtube-dl -F and then let us use ffmpeg and youtube-dl to do it all with options in the background.


I love it!


Always had been very good in using this addon.
Looking forward to the new campatible version for Firefox Quantum!


As of version 5.7.36 (dec 2017), 480p download is broken (only a small chunk of mp4 is actually downloaded and video doesn’t mux)... Will there be continued updates for non-Quantum users?...


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