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@coolboymew @vriska Tumblr might support the ActivityPub protocol eventually: "Automattic CEO Matt Mullenweg tweeted in November 2022 that Tumblr was adding support for ActivityPub interoperability, in response to a user's complaints about Mastodon's complexity. However, no further information was revealed for over a year, and the project was expected to be cancelled after a leaked reorganization that moved most of Tumblr's staff to other Automattic projects. However, following a question from a TechCrunch reporter during a questionnaire about the leaked memo, he revealed that the interoperability feature was not cancelled and that there was a small team working on studying the potential of implementing the protocol. The plan was once again affirmed by Automattic in January 2025, with the ActivityPub plugin for WordPress most likely being the main method used for interoperability with the fediverse." https://en.wikipedia.org/wiki/Fediverse#Adoption
However, this might be due to the fact that the value of Tumblr dropped by over 99%: the current owner(s) might just be experimenting with random things in a non-committal way in the hopes that something they try happens to get money coming in again. "The sale was for an undisclosed amount, but Axios reported that the sale price was less than $3 million, less than 0.3% of Yahoo's original purchase price." https://en.wikipedia.org/wiki/Tumblr