God, What the h--l? Who the crap would share their Guinness????????????
And by the way, what the heck is the little plastic thin in the bottle!!!!!!!!
LOL....
I didn't happen to see the little plastic thing, but there is a thing called a "widget" that Guinness puts in their cans that carbonates the beer once it is opened. It's about 3/4" round and white. Guess they put it in bottles now, too.
Oh, and the only way to drink Guinness is on tap, properly poured of course. It's an art.