Many thanks to Dishita for his great work and recommendation to try the beta version of the desktop app, since the add-on was banned from YT a month ago.
I didn't use all the features yet, but the desktop app seems to work fine on my Mac, no issue encountered so far.
I would like also to underline that the add-on was working good with Firefox as well until it was banned from YT, no matter if you made donation or not.
I'm looking forward to the official release of the desktop app.

A few words to the users who are blaming Dishita that the add-on doesn't work.
TRY THE DESKTOP APP

Unfortunatley Youtube has again made this extension unusable, I keep getting an error message, "invalid data found". No video can be downloaded, not shorts not regular, nada.

I thank DIshita for all these years providing this app. I paid quite a few times for support, because of the enjoyment I received. Now the bad part, the last time I paid over 3 months ago, nothing has worked. I, along with 100,000's of others would like some transparency.
It doesn't work on Mozilla.
Until then, you get this low rating, as it's a useless app.

Cet module ne fonctionne plus depuis un moment. Dommage !

The best for downloading YouTube products

This add-on has not worked for awhile and Dishita hints that you donate or upgrade to the Pro version. People have done that and end up feeling ripped off. Firefox still recommends this add-on? That's insane! I and others have brought this to their attention and still they do nothing which tells me they don't give a xxxx!
I too have seen the anonymous 5 star reviews. I'm going to call it as I see it - they're fake!
Dishita now hear this! You obviously have no intentions of fixing the add-on so why don't you just come out and say so? Have you no balls to face this issue? Looks like you don't...

Well it was worth the wait as now that the bugs have been cleaned out the interface works seamlessly on Windows10 and is a reliable and fast add on to use.

Is very nice extension, i love it and is workng perfectly on My MX Linux 23,4 x64 Libretto XFCE, operating system, i have follow the instruction of the MX Linux website for install the AppImage program for Linux and is working.

Is working nice for the Windows user to, but me i am only on Linux, Windows is end for me, to much problem with Windows system, Linux is better, no virus, no need to pay a licence for the operating system and the programs, all is avalable for free, no file lock problem, nothing of that.

Only open source and free and very nice stuff.

Windows = 0 And Linux = 1

For this extension, and the desktop program version, the desktop version is working better, the extension is bug and stop to working to appear the download option, but the desktop version is working nice with all public vesion of the video, but for the private video, i have tery to connect to my youtube account and try the trick of the cookie for unlock the access to download private and restricted video and is not working, i don't know what i need for make this working for me.

And another last thing, i don't know what is me Pro key for the activate the pro version of the desktop program, because, the developper i never send me in email me key for the program, i am pay $43,82 CAD - $30,00 USD for buy one pro licence key for me and i am never recive in email my pro key, i have pay ad i not have me key, is not good and is not correct.

To the developer of this extension and this desktop program, send me me valid pro key for activate the pro version of the full version of the next updated full version of the program, i have pay for that, i need it.

It's now six-months since the Developer acknowledged the changes made by YouTube, and promised a fix. A further message again promising a fix was posted in October. Hollow promises.

Given there are now decent alternatives available that work perfectly well, including 720p, it's unlikely this utility will be updated again and is now 'dead in the water'.

Sorry Dishita, but leaving users hanging for over six-months with a product that no longer works along with unfulfilled promises is wholly unacceptable.

Users at this stage now need to report the add-on to Mozilla, and have them remove it. It's little more than taking money under false pretences.

It doesn't work anymore.

Has been broken for months but there are swath of anonymous accounts giving it a 5 star rating. Whatever you do, don't waste your money buying the pro version like I did.