Like a previous anon said, I also think she simply like the drawing, as she light heartingly has given the finger in the past at comic-cons for fan photos. *shrugs*

It’s a possibility, but I think we can all agree that if it was just that, the timing is really bad. And still, usually, when she likes some fan art from Tumblr, she tweets it, post it on Instagram and credits the author. That’s not what she did, so we can legit assume this icon is for us too.