Pretty good, even though it needs some polishing like changing the player and other inconsistencies.

and for Firefox 2.0 ????

Excellent add-on. Unfortunately, it doesn't save settings (at least in private windows that is). I'm using FF portable, but I don't think that's the issue. If this gets fixed, it would be excellent, it just resets the settings on browser restart every time when you use private windows by default. I haven't tried regular windows.

Very good extension. But one problem has appeared recently: the drop down menu is trying to display the options in a wider format than the menu allows, so half the menu is cut off and inaccessible. I've turned each of my other extensions off individually and checked to see if one of them was interfering, but nothing worked. Here's a link to an image of what the drop down menu is doing.
https://ibb.co/kg0jkHm

since yotube has been changing I had two others addons that stopped working, was looking for an addon that can change the player size and this one does the job the only bad? thing is that there is a blank space between the player/comments and the right sidebar

please add 'sort by' option for videos. there is already a small addon 'youtube-sorter', which works partially.