少し時間がかかる場合がありますが、簡単で使いやすいので愛用しています。

trims

A really good YT downloader. I've used it for a while and recommend it highly.
Yes, you have to read and use the very simple instructions. Aren't you worth it?

It's helpful. the developer is working to fix any bugs that arise.

This extension actually works and is simple to use. Unfortunately the 1080p bit is a bit hit and miss, more miss than hit, but still streets ahead of others I have tried. The 1080p situation is a bit annoying as I contributed cash to enable it.

this addon works pretty well downloading films.
It's only two things that could be better:
- I have to do the naming in advance (it's not done automatically but name is youtubevideo.mp4 or so) and:
- sometimes it takes quite a while (in this time I have to watch the film) until I can sent the download to downthemall (have to wait, close and open it a few times until it works)
I'm sorry for the bad reviews of people who cannot wait 3 days until the changes of youtube (wich lead to no download possible) have been fixed.
Good work!

Excellent and very easy to use.

it work!!!

Work-around for missing download button (thanks Rosa)
...(display YouTube video page)
Tools > Browser Tools > Web Developer Tools (or ctrl-shift-I)
Inspector (tab)> Search HTML (field)> #eytd_list (press enter)
...(displays 1 of 2)
(press enter)
...(displays 2 of 2. box at right: element display: none)
highlight "none" > change to "block"
...(displays popup upper left with download options)
select an option
...(displays "Save As" dialog)