Someone falsely inserting the Johannine comma. It was not Jerome. Someone falsely pretending to be Jerome to falsely insert scriptue.
This is a first-person letter to Eustochium
You claim it is a forgery without any idea who, when, where?
And you actually claim the whole purpose of the Prologue was to insert the heavenly witnesses ???
And it got passed the study of the learned Victor of Capua.