Fr. Paul Kramer holds that John of St. Thomas misrepresented St. Robert Bellarmine's position:
".....while John of St. Thomas is correct insofar as he says Suárez maintained that if 'a pope is a manifest heretic & declared incorrigible, he is deposed immediately by Christ the Lord, and not by any authority in the Church,' he erred by attributing this opinion to Bellarmine, since that is not what Bellarmine taught. Bellarmine says nothing anywhere about any need for the pope to be declared incorrigible for him to fall from office; but rather, he says that once the pope manifests himself to be pertinacious, he immediately falls from office entirely by himself ipso facto; and not mediately by the dispositive agency of anyone else’s declaration, but 'by himself', and 'without another external agent' (sine alia vi externa). John of St. Thomas was guilty of sloppy scholarship in his treatment of Bellarmine here....."
Kramer, Paul. On the true and the false pope: The case against Bergoglio (p. 142). Gondolin Press. Kindle Edition.