I downloaded the Trisquel 5.5 iso(from March 6) and then installed
"gnome-session"(package with gnome-shell and other dependencies).
It worked perfectly on my hardware (Intel Core i3, 4GB DDR3 RAM) and 1080p
videos on Youtube HTML5.
Screenshots:
(desktop)
http://ompldr.org/vY3ljaQ
(YouTube with Sintel 1080p)
http://ompldr.org/vY3ljYw
http://ompldr.org/vY3ljZA
(activities)
http://ompldr.org/vY3ljaA
http://ompldr.org/vY3ljZQ
http://ompldr.org/vY3ljZg
(applications - abrowser, libreoffice)
http://ompldr.org/vY3ljZw
