summerized= Basically bypass ALL browsers ... and enter url into a player!
I may be stating the obvious to many of you here but 4 years into using Ubuntu it has just dawned on me that it is easy to view Youtube videos so they do not check appallingly with Flash; Pepper and other Gnash ....
and smooth; no checks !
will only play up to 1280x720 but that is quite good [if anyone knows how to go higher 1920x1080 or even 4k please say] i think youtube changed the way it delivers videos [DASH]hence limitation for terminal playback; both mpv and vlc only play the mp4 and do not "see" the DASH
Available formats:22 : mp4 [720x1280]
18 : mp4 [360x640]
43 : webm [360x640]
5 : flv [240x400]
36 : 3gp [240x320]
17 : 3gp [144x176]
136 : mp4 [720p] (DASH Video)
135 : mp4 [480p] (DASH Video)
134 : mp4 [360p] (DASH Video)
133 : mp4 [240p] (DASH Video)
160 : mp4 [192p] (DASH Video)
140 : m4a [128k] (DASH Audio)
171 : webm [128k] (DASH Audio)
or you can use mpv again easy AND navigation is easier faster
or not as simple [that i know of]
mplayer [requires youtube-dl installed too]
mplayer -fs -cookies -cookies-file /tmp/cookie.txt $(youtube-dl -g --cookies /tmp/cookie.txt "Your_YouTube_url")
Again probably obvious to many ... but as i said i for one never thought of it before ::}}
mpv cvlc mplayer [for me here in order of smoothness]
EDIT also use Bomi smooth fast stable