According to Toller :

You are correct that it normally carries nothing, but why would a breaker
open on a ground fault? (unless it is a gfci...)

A ground fault is simply a leak to the grounding conductor - it could
be a few milliamps, or many amps.

Breakers trip on big ones. GFCIs trip on small ones.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.