Wikipedia has a sentence in its article on ellipsis:

In reported speech, the ellipsis is sometimes used to represent an intentional silence, perhaps indicating irritation, dismay, shock or disgust. This usage is more common amongst younger, Internet-savvy generations.[citation needed]

I can find plenty of random internet articles making a similar statement, but is there an actual authoritative grammar source that says this is grammatically correct? Is it just something the "Internet-savvy generations" have invented?

Here is an example from a story:

She swallowed hard. "I'm afraid, Mark. Maybe if you might... talk to him?"

Here the ellipsis is indicating a verbal hesitation in the quote rather than the typical use of indicating an omission.