Some features are nice, however the pop out viewer leaves MUCH to be desired.
You cannot seek, which sucks.
But the WORST part? No captions. The captions do not show in the pop out at all. This makes the video inaccessible to me. If possible, I would appreciate a fix at some point. Pop out is currently essentially useless to D/deaf/Hard of Hearing folk like me.

Extension has been nearly unusable for the past 2 months. Half of the time it's just not straight up loading when you open a YouTube page directly from a link.

not working atm

It appears addon is missing a "list view" option to list videos on YouTube channels under each other instead of the ugly YouTube-Polymer forced "roster" view.

I use this extension on my laptop, but it won't load on my t mobile phone...really sucks

Remove the sponsor.

I need to change my rating and opinion on this. I still like mini player, same as flip horizontally and hide end screens. But reverse the order of a playlist is not working how I wanted it to work. In fact, it's practically not working, because I do not see any icon, nor in player or playlist and also as I now understand, it's only working with pop-up player, which is not working either.

So yeah. For mini player, flip horizontally and hide end screens, this add-on gets two stars, but the rest have no practical use for me or are not working.

In version 2.0.17 the option " Use the available space based on the viewport dimensions to expand the video player " doesn't resize the video correctly, it's taller than the viewport and the control bar is displayed off screen.
Now has ads.

It's amazing how extension to block the ads shows its own ads after update now.

A lot of useless features, but no Closed Captions.

What is the cost of adding one more checkbox for Closed Captions ?!!

Interesting concept ruined by unbelievably bloated execution.

Downloaded solely for the default volume option and to disable default auto-play; the latter works - the former doesn't.

In practice, videos load and begin playing too quickly - before the extension can modify (lower) the volume. Maybe it'd work better if my PC were a potato or my browser ran like crap, but for obvious reasons I'm going to skip that test and go back to using a simple script for what I need.

Has a few other features that might be interesting in very niche scenarios, if they actually work, but nothing that either your average end-user nor your function-minded power-user will care about. Get rid of all that garbage and optimize the remaining code, and maybe this'll be worth trying again.

For now... hard pass.

while the features are good half the time it does not allow me to play the videos, I keep refreshing page and pressing on the play button and its been more than 4 months. I wonder if anyone reported it or the devs are simply not updating it anymore.

Not sure when this started, but this add-on seems to prevent videos from beginning at the correct time when there's a timestamp in the YouTube link. i.e. If you go to a link that says https://www.youtube.com/watch?v=[video]&t=574s, the video will just start at the beginning instead of starting at 9:34. This problem went away as soon as I disabled this add-on.

the latest updates did nothing but detract from the add-on and worsen the experience. one made it so you have to click farther away to access the add-on's buttons, the other made it so you need another click before you can access them in the form of a triple dot icon. and finally expanding the video player does not work correctly most of the time ever since these updates rolled out. i don't know why they're doing this but this used to be my #1 extension. now i'm forced to roll back to out of date versions.

I hate the new version, is intrusive with the UI and override the youtube options/behavior. I still using this, just for the cinema mode.

last update changed everything I liked about this add-on, removing now :(

was good but I hate the new version, I really miss the tool bar

Recent update made it not worth the effort to keep enabled.
Extension settings now override youtube ones, instead of adapting them. If you turn the autoplay toggle off, it still keeps autoplaying since the extension's checkbox for autoplay doesn't update.
Having videos be auto-paused in new tabs until you click them behaviour changed, now you have to click the youtube icon in the centre of the video instead of just clicking anywhere on the video. Overrides youtube specified theme with the extension one. If it's not going to respect changes made to settings using the buttons on the youtube page, it should at least hide those buttons.

Was working absolutely fine until the update, now experiencing all sorts of problems. Like the old saying goes " if it isn't broken, fix it until it is!" Had to disable it.
Edit: Reinstalled Version 2.0.101 from here, https://addons.mozilla.org/en-GB/firefox/addon/enhancer-for-youtube/versions/ and everything appears to work as before, turned off auto updates for the time being. Will update when fixed.