Great Idea, good add-on.
I would like to see a button in the symbol bar in order to have easy access to the add-on (activating and deactivating the add-on). This feature would be very nice.

BEST ADD ON EVER! I have always been looking for something like this! OOOOhhh myyy gooosh. FINALLY!!

Little bit surprised by the low amount of users, but eager to have less addictive stimuli, I simply tried: it gives on what is it promises. No more youtube with unneeded stuff.