I went to a site today that had a full page cookie popup. When I clicked manage cookies to disable, it presented me with a a choice of "eagerly interested" and "consent". WTF is that? I didn't see the opt out option right away so i just left the page.
Just search for how to disable cookies and cookie banners; it's native functionality as of this year far as I can tell, you may habe to update a config setting, sorry have only been on FF a few months.
I also have privacy badger and Ghostery installed for movies and ublock on desktop, try exploring those if you can't get FF to do natively.