In my humble opinion I think that while Firefox has asked some ground in market share, does a great job with the web and compete against the negligent microsoft products had 8 years to give us a better browsing experience we know today has much to do calving with Firefox.
Yeahh Youtube is business no other thing, All us viewed TV with ads all life and now stay here, share knowledge and opinions. If you have all Wallstreet over your shoulders, sure you search the form to increase the revenue. For other side if you don't want to pay viewing the ads, simply install adblock plus.
I haven´t used Bootstrap, but Hacker News Community always impulse to test the "new" ways and technologies for solve the "problems". So get one's hands dirty!