The humbling reversal on one of the most sensitive policy issues facing the social network came as Twitter encountered user revolt for the first time as a public company.
Under the short-lived change on Thursday, a blocked Twitter user could view or tweet at the person who blocked him or her, but that activity would have been rendered invisible to the victim as if the offending account did not exist.
Under the re-instated policy, users could prevent their harassers from following them or interacting with their tweets. Users are also explicitly notified if they are blocked.
Before it backtracked, Twitter had said Thursday that the change was meant to protect victims of harassment who wanted to filter out abusive messages but feared that the act of blocking a user would prompt retaliation.
“We have decided to revert the change after receiving feedback from many users – we never want to introduce features at the cost of users feeling less safe,” vice president of product Michael Sippey wrote in a blog post.