X community adds a context note to Sen. James Lankford's post: Sen. James Lankford (R-OK) posted "All of the 9/11 attackers were present in the US illegally. We shouldn’t wait until the next horrific terror attack to realize that our wide-open southern border is a national security risk." The X community added a note to the post that read: "Readers added context they thought people might want to know. This is false. All the 9/11 hijackers arrived legally. The US 9/11 Commission plainly stated this as well. And of the 19 hijackers, four were in the US beyond their visa expiry date i.e. an overstayed visa but even that isn't immediate grounds for removal. govinfo.gov/content/pkg/CH… govinfo.library.unt.edu/911/report/911… factcheck.org/2013/05/911-hi… gao.gov/new.items/d114… travel.state.gov/content/travel…" The label is part of X’s Community Notes system. X users are able to sign up as contributors to add context to posts. X owner Elon Musk shared that any post with a Community Note added to it will be demonetized. The Community Notes account on X also posted that notices will be pushed to users who previously engaged with a post when a Community Note is added to it later.