https://thenextweb.com/tech/2018/12/05/tumblrs-new-porn-banning-algorithm-isnt-working/

On Monday, Tumblr announced that its site will block anything it considers to be adult-rated visual content that’s NSFW — a category including porn, GIFs, and “female-presenting nipples.”

Tumblr explained its decision to clamp down on NSFW material in a blogpost: “Adult content will no longer be allowed here. While we do not judge anyone for their desire to post, engage with, or view this stuff, it is time for us to change our relationship with it.”