This rainbow like will be available throughout the month of June. To activate it, you simply have to connect to your Facebook account, to visit https://www.facebook.com/LGBTQ/ and to click on "like". The new emoji will then be available.
Note that other networks like Instagram and Twitter have launched their own initiative. On Twitter, you can already see the #Pride 2017 or #loveislove that continues to work this year. On Instagram, the #KindComments made its appearance with photos featuring rainbow colors to promote tolerance throughout the world.