They just mean a marketing campaign aimed at developers. It looks like the person who made the Mastodon post had a Twitter developer account, and Twitter sent t

They just mean a marketing campaign aimed at developers. It looks like the person who made the Mastodon post had a Twitter developer account, and Twitter sent them an email saying, "Hey, developer! Now seems like a great time to build some stuff with the Twitter API!" I'm assuming this was something designed ages ago and someone forgot to turn it off, but the hashtag they chose for the background of the email-marketing image – #whatshappening – is on point, as I'm sure that's what every developer who uses the Twitter API has been saying. On the other hand, I see the developer site is back up. If this is indeed a new marketing campaign, it's a brash move.