Does not work in any version of the firefox browser.

did not actually work. videos still loaded at normal size and 360p despite my settings saying theater mode and 1080p

doesn't change videos to high resolution.

I've tried a every couple of months for past few years, never worked. I use stable branch.

Not working

Doesn't actually do anything to youtube videos.

Not work anymore, even update not helped

It doesn't work on Android

É simplesmente inútil. Coloquei na extensão para abrir vídeos do youtube como 1080p HD mas todo vídeo está abrindo como 720p mesmo tendo a poção de 1080p. É simplesmente inútil e um completo desperdício de espaço.

doesn't work and affect youtube at all, anymore

Broke so many videos to the point I wanted to remove it. However, I realized I couldn't remove it! So I disabled it to keep watching youtube, but another problem came up! It turned ITSELF back ON! Probably spyware and will 100% break youtube.

Pointless. Does not work!

Isn't functioning

Currently breaks YouTube videos

Automatically setting the video quality to the user's liking does not work anymore on Firefox For Android 130+.

changing default speed doesn't work

Ghost module that absolutely does not work.
There is no need to waste time writing these modules if the result obtained is zero.
Someone will have to explain to me where the recommendation of this module comes from, I have trouble understanding.
I remove it and we will not talk about it anymore.
Linux MAGEIA 9.0
FF 115.13.0esr 64 bits

Doesn't do anything on firefox mobile on android.

Does not work at all, Why still recommended?

Set to 1080p, but playing at 720
(URL: https://www.youtube.com/watch?v=tnu571p2CCw)

See here for the only addon working:
https://addons.mozilla.org/de/firefox/addon/hd-quality-toggle-for-youtube/