Adding styling to a new blockContent separator in Slack thread

Hi! I’m trying to extend blockContent by adding in a new

style

, a separator that returns an

<hr />

. I added this in and it works:

{ title: "Separator", value: "hr" },

– but is there a way to specify styling for this element? Basically some kind of preview so that my editors can know that that blank line is a special blank line?

I mostly figured out how to do this – adding
but the

separatorRender

, a React component that returns a styled

span

, is applied both to the text in the editor and to what’s in the drop-down menu in the editor toolbar. Is there a way to address these separately?