lactivist
A lactivist is someone who says they're an activist but only when it's easy, like on social media, and never when it matters.
My friend is a lactivist. She posted about breastfeeding but never showed up to the protest.
A lactivist once tweeted about breast milk but never left their house to support it.
A lactivist yelled at a man for not liking breastfeeding, but never stood up for it when it mattered.