Guess I should give a reason as to why you'd want to do this.
Some of us use to use youtube.com/tv but as anyone that used it knows now they supposedly shut that down. Actually they didn't shut it down. The youtube app in things like your smart tv or roku is nothing but a webpage. They simply started checking user-agent strings of browsers to excluded desktop browsers from accessing the site by re-directing them to the normal youtube site. If you change your browsers user-agent string to mimic one of these "smart streaming devices" the youtube.com/tv works perfectly fine on desktop. I have tested this.