Insert commas between query results?

I’ve got a query that returns a set of tokens, but I’d like to insert a comma between the tokens, like so:

Alpha, Beta, Gamma, Delta

I’m using a Basic Text block to style the tokens, and I can insert a comma there, but then the result will be:

Alpha, Beta, Gamma, Delta**,**

with a useless trailing comma at the end.

How can I insert characters just between the results and not before or after?

TIA!

Hello!

This is working fine for me.

%root%:not(:last-child):after{
  content: ',';
}

Basic setup, query with post titles.

image

Result:

image

Worked like a charm, thanks!