GR does not displace SR, it builds on it. SR stipulates some basics which are by no means contraverted by GR, and E=mc2 is among these.
QM accommodates itself very readily to SR, and this is all that is required to understand what is being claimed in the article.
Isn't this significant? Wasn't Einsteins quest to find a way to bridge the gap btw relativity and quantum mechanics?