https://techcrunch.com/2018/12/03/tumblr-no-more-porn/

Tumblr, a microblogging service that’s impact on internet culture has been massive and unique, is preparing for a massive change that’s sure to upset many of its millions of users.

On December 17, Tumblr will be banning porn, errr “adult content,” from its site and encouraging users to flag that content for removal. Existing adult content will be set to a “private mode” viewable only to the original poster.