The feature will be an “improved version” of the existing search feature and will allow users to search through their entire DM history, not just recent messages. The company is also working on the ability to search the content of messages, rather than just the sender. That update is coming “later this year.”
These may sound like relatively minor updates, but the inability to efficiently search direct messages has long been a pain point for anyone who uses the feature heavily. Trying to find a months or years-old message was nearly impossible unless you were willing to endlessly scroll through old chats to find it. But with the new search bar, searching Twitter DMs will hopefully be more like any other messaging app.