Preventing banned users from creating new accounts and changing its search tool to minimize blocked accounts are among the new steps Twitter is taking to prevent "the most prevalent and damaging forms of behavior" on its social media platform.The moves come months after Twitter gave its users new ways to mute and report abusive posts, as NPR's Alina Selyukh reported in November.Saying that Twitter wants to ensure freedom of expression while also preventing abuse and harassment, the company's vice president of engineering, Ed Ho, unveiled three changes Tuesday that will either block abusive users from their targets or help other users avoid seeing abusive content."We're taking steps to identify people who have been permanently suspended and stop them from creating new accounts," Ho wrote on the company's Twitter Safety blog.The list of people who've been permanently suspended from Twitter includes conservative commentator Milo Yiannopoulos, whose ban followed a campaign against Ghostbusters actress Leslie Jones last summer. At the time, Yiannopoulos denied any wrongdoing and said his suspension was political.Two other new changes will alter how some tweets are displayed, or how they appear in a search.Twitter's "safe search" tool promises to remove from search results any tweets "that contain potentially sensitive content" as well as those from blocked or muted accounts. Ho says that the "content will be discoverable if you want to find it."Another upcoming new feature would "collapse" potentially abusive or low-quality replies to a conversation, grouping the lower-rated replies together and displaying them beneath a batch of the most relevant responses.The social media platform's attempt to curb abuse reflects what NPR's Terry Grosscalled a "paradox" in the company's platform last autumn: