Reactjs : Invariant Violation: ReactMount: Two valid but unequal nodes with the same `data-reactid`: .0.5
This is a known issue : https://github.com/facebook/react/issues/1466
Using <div contentEditable dangerouslySetInnerHTML={{__html: '<p></p>'}} /> is the only workaround for instance.
I had similar problem and I solved this problem using key = {some random string} for new element.