Bradley Cooper made a low-key appearance at this years Oscars, a year on from his show-stopping performance of " Shallow" alongside Lady Gaga.Cooper produced Joker, which is nominated in 11 categories this year and has so far won one award for Best Score.Joker composer Hildur Guðnadóttir thanked Cooper in his acceptance speech.Remember A Star Is Born? That was only one year ago, guys.