Mark Ruffalo is amongst the many celebrities and fans, who took to social media to pay a heartbreaking tribute to Chadwick Boseman, who would have been 44 on November 29, 2020. The Black Panther star sadly passed away in August this year after a four year battle with colon cancer, as revealed by his family in a statement on Twitter."Thinking of your passion, love, and your light today, @ChadwickBoseman.