Twitter has long had a policy of �use it or lose it' when it comes to usernames, but it's not been actively enforcing it until now. The company has been sending out emails to owners of inactive accounts telling them so sign in by December 11, "otherwise your account will be removed from Twitter."

There's an interesting byproduct of this: old usernames will become available as users are removed. Twitter says that this will be a gradual process, so there won't be a big name land grab on December 12. It's also not clear what will happen to old followers.

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"As part of our commitment to serve the public conversation, we're working to clean up inactive accounts to present more accurate, credible information people can trust across Twitter," the company said in a statement. "Part of this effort is encouraging people to actively log-in and use Twitter when they register an account, as stated in our inactive accounts policy."

The company says that accounts that have not logged in for over six months will have received the email. "Of course, inactive usernames will become available as a result of this work. This group of inactive accounts will be removed over many months - not all at once."

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This raises some interesting questions. Are all accounts treated equally - even high profile ones that have just given up, for whatever reason? Mark Zuckerberg's account has over 463,000 followers, but hasn't tweeted since 2012, for example. The same is true of the Obama Twitter archive, which has been silent since 2017.

Some Twitterbots, meanwhile, seem to have had emails, while others have not.

And then there's the thorny issue of what to do with accounts that stopped tweeting because the owner has passed away. Twitter currently has no way to memorialise an account like you can on Facebook, but the company is considering its options. A spokesperson told The Verge: "We do not currently have a way to memorialize someone's Twitter account once they have passed on, but the team is thinking about ways to do this."