Twitter community adds a context note to Joe Biden tweet:  The official Twitter account for the president tweeted, “Look, I think you should be able to be a billionaire if you can earn it, but just pay your fair share. I think you ought to pay a minimum tax of 25%. It’s about basic fairness.”  The tweet included a quote meme that read “You know the average tax billionaires pay? THREE PERCENT. No billionaire should be paying a lower tax than somebody working as a schoolteacher or a firefighter. - President Biden." Twitter added a label to the post that read "Readers added context they thought people might want to know.” The added context read "The 25 highest-earning billionaires pay an average tax rate of 16%. Meanwhile, among households earning from $50,000 to $100,000 a year — the category that many teachers and firefighters would fall into — the vast majority paid lower effective tax rates of between 0% and 15%." The context note also included a link to a PolitiFact article rating his claim "False." The label is part of Twitter’s Community Notes system. Twitter users are able to sign up as contributors to add context to tweets.