See https://www.adl.org/blog/how-the-ok-symbol-became-a-popular-...
The “OK” hand gesture originated as one of these hoaxes in February 2017 when an anonymous 4channer announced “Operation O-KKK,” telling other members that “we must flood Twitter and other social media websites…claiming that the OK hand sign is a symbol of white supremacy.” The user even provided a helpful graphic showing how the letters WP (for “white power”) could be traced within an “OK” gesture. The originator and others also suggested useful hashtags to help spread the hoax, such as #PowerHandPrivilege and #NotOkay.